Regulation of metamorphosis in holometabolous insects

May combine two claims.

The JH insensitivity of Drosophila larvae is evident from manipulations that prevent JH production, prevent JH action, and from mutants null for Kr-h1.

“The JH insensitivity of Drosophila larvae is evident from manipulations that prevent JH production by killing the corpora allata [41,50], prevent JH action by removing the redundant JH receptors, Met and GCE [1], and by mutants that are null for the main JH effector, Kr-h1 [49].”

• cites [41] Mirth, 2014, Juvenile hormone regulates body size and perturbs insulin signaling in Drosophila, Proc Natl Acad Sci USA sourceDisputed

  The paper does use corpora allata ablation to prevent JH production, and reports that loss of JH does not affect the timing of the metamorphic molt. But its opening summary and the section on larval growth report that ablated larvae grow more slowly and reach a smaller size, contrary to the cited sentence’s unqualified claim of JH insensitivity. (LLM, conf=0.89)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites [50] Riddiford, 2010, A role for juvenile hormone in the prepupal development of Drosophila melanogaster, Development sourceDisputed

  The cited paper does kill the JH-producing corpora allata, but its Discussion reports that the resulting larvae have reduced growth that JH treatment rescues—evidence against larval JH insensitivity. It also cautions that normal molts in these larvae cannot establish whether JH is required for larval molts. The Met/GCE and Kr-h1 clauses carry separate citations and are not judged here; page numbers are unavailable in our copy. (LLM, conf=0.87)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites [1] Abdou, 2011, Drosophila Met and Gce are partially redundant in transducing juvenile hormone action, Insect Biochem Mol Biol sourceNot checked — no full text of the source
• cites [49] Pecasse, 2000, Krüppel-homolog, a stage-specific modulator of the prepupal ecdysone response, is essential for Drosophila metamorphosis, Dev Biol sourcePartly supported

  The section “Kr-hα Modulates the Prepupal Ecdysone Response in Salivary Glands” (page unavailable) says larval development proceeds normally in the Kr-h1 mutant despite the absence of Kr-hα transcripts. But “Kr-h Transcripts Have Stage-Specific Functions” says these surviving mutants retain adequate Kr-h transcript levels, while a deletion of Kr-h causes embryonic or early-larval lethality. The paper therefore supports normal larval development after loss of Kr-hα, not the claim that Kr-h-null mutants demonstrate insensitivity to juvenile hormone. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

May combine two claims.

Late-stage Tribolium larvae become JH-sensitive, whereas Drosophila larvae do not.

“The two species differ in that late-stage Tribolium larvae become JH-sensitive, whereas Drosophila larvae do not (Figure 3a).”

• cites [41] Mirth, 2014, Juvenile hormone regulates body size and perturbs insulin signaling in Drosophila, Proc Natl Acad Sci USA sourcePartly supported

  The introduction (page unavailable) says that feeding JH to Drosophila larvae delays metamorphosis only at very high concentrations, and the Discussion says JH does not affect their critical weight. This supports a limited claim about Drosophila’s developmental response, not the unqualified statement that its larvae are JH-insensitive. Our copy does not address late-stage Tribolium larvae or compare their JH sensitivity with Drosophila’s. (LLM, conf=0.85)

  Experimental — accuracy not yet measured
• cites [50] Riddiford, 2010, A role for juvenile hormone in the prepupal development of Drosophila melanogaster, Development sourceDisputed

  The Abstract reports that feeding a JH mimic to third-instar Drosophila larvae, or applying JH at the onset of wandering, reversed the effects of JH loss. The Discussion likewise says these effects could be rescued during the third instar or early wandering. Thus, the paper reports late-stage Drosophila responsiveness to JH, contrary to the claimed contrast. (LLM, conf=0.89)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites [1] Abdou, 2011, Drosophila Met and Gce are partially redundant in transducing juvenile hormone action, Insect Biochem Mol Biol sourceNot checked — no full text of the source
• cites [49] Pecasse, 2000, Krüppel-homolog, a stage-specific modulator of the prepupal ecdysone response, is essential for Drosophila metamorphosis, Dev Biol sourceDisputed

  In “Kr-h Mutants Display Developmental Defects during the Prepupal Stage” (page unavailable), the paper says that topical juvenile hormone applied to late Drosophila larvae or prepupae produces a differential developmental response. That contradicts the claim that late-stage Drosophila larvae do not become JH-sensitive. The paper does not address the comparison with Tribolium. (LLM, conf=0.86)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured

May combine two claims.

In Tribolium, JH, working through Kr-h1, represses E93 expression, but it has no effect on broad.

“In Tribolium, JH, working through Kr-h1, represses E93 expression, but it has no effect on broad [64].”

• cites [64] Ureña, 2016, The occurrence of the holometabolous pupal stage requires the interaction between E93, Krüppel-homolog 1 and Broad-complex, PLoS Genet sourceDisputed

  The Results section confirms that TcKr-h1 represses TcE93 at the larval–pupal transition. But the Discussion says JH represses Broad-Complex (Br-C) in young holometabolous larvae and that Kr-h1 also affects Br-C expression in a stage-specific way, contrary to the claim that JH has no effect on broad. (LLM, conf=0.88)

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured

May combine two claims.

Later larval molts use JH via Kr-h1 to maintain larval molting and suppress E93 expression until larvae cross a size threshold for metamorphosis.

“but later ones use JH (via Kr-h1 ) to maintain larval molting and suppress E93 expression until larvae cross a size threshold for metamorphosis.”

• Also stated in: § The endocrine landscape for growth and metamorphosis · p. 3 · plain

  “A competence factor causes the juvenile to become JH-sensitive, and JH is thereafter required to maintain the juvenile condition (e.g. [12,51]).”

• cites [12] Daimon, 2015, Knockout silkworms reveal a dispensable role for juvenile hormones in holometabolous life cycle., Proc Natl Acad Sci USA sourcePartly supported

  The introduction says JH’s antimetamorphic action is needed in later larval stages until larvae reach an appropriate size, and the Gene-Expression Analysis shows that JH signaling induces Kr-h1. The paper does not show that this pathway suppresses E93 expression; its analysis of metamorphic gene expression focuses on broad instead. Page numbers were not available in the supplied passages. (LLM, conf=0.87)

  Experimental — accuracy not yet measured
• cites [51] Smykal, 2014, Importance of juvenile hormone signaling arises with competence of insect larvae to metamorphose, Dev Biol sourcePartly supported

  The Conclusions (page unavailable) say that the JH–Met–Kr-h1 pathway becomes increasingly important in later instars for preventing precocious metamorphosis. They discuss critical body weight, but say the study does not establish whether size is the signal for metamorphic competence. The paper examines repression of BR-C, not E93, so it does not support the claimed suppression of E93 or a definite size-threshold mechanism. (LLM, conf=0.91)

  Experimental — accuracy not yet measured

May combine two claims.

Chinmo is anti-metamorphic and suppresses the expression of broad and E93.

“Chinmo is anti-metamorphic and suppresses the expression of broad and E93 .”

• Also stated in: § Interaction of metamorphic genes with the endocrine landscape Maintenance of the larval stage · p. 4 · plain

  “Chinmo maintains the larval state in both Drosophila [59,7] and Tribolium [30], and it inhibits both broad and E93 expression .”

• cites [59] Truman, 2022, Chinmo is the larval member of the molecular trinity that directs Drosophila metamorphosis., Proc Natl Acad Sci USA sourceSupported
• cites [7] Chafino, 2023, Antagonistic role of the BTB-zinc finger transcription factors Chinmo and Broad-complex in the juvenile/pupal transition and in growth control, eLife sourceSupported
• cites [30] Khong, 2024, The BTB transcription factor, abrupt, acts cooperatively with chronologically inappropriate morphogenesis (Chinmo) to repress metamorphosis and promotes leg regeneration, Dev Biol sourceNot checked — no full text of the source

May combine two claims.

A competence factor causes the juvenile to become JH-sensitive, and JH is thereafter required to maintain the juvenile condition.

“A competence factor causes the juvenile to become JH-sensitive, and JH is thereafter required to maintain the juvenile condition (e.g. [12,51]).”

• cites [12] Daimon, 2015, Knockout silkworms reveal a dispensable role for juvenile hormones in holometabolous life cycle., Proc Natl Acad Sci USA sourcePartly supported

  The Development of JH-Deficient Mutants section reports that JH-deficient silkworms maintained larval status in the first two instars but could metamorphose precociously after the third, supporting a later role for JH in maintaining that status. The Significance and Discussion sections propose an unidentified competence factor for metamorphosis; they do not establish that it causes juveniles to become JH-sensitive. Page numbers are unavailable in our copy. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites [51] Smykal, 2014, Importance of juvenile hormone signaling arises with competence of insect larvae to metamorphose, Dev Biol sourcePartly supported

  The Conclusions (page unavailable) propose that, as larvae acquire competence to metamorphose, JH signaling becomes important for preserving their larval character. But the paper does not establish a competence factor that causes JH sensitivity: it says the nature of the competence signal is unknown, and the Discussion reports a functional response to JH in early instars. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

May combine two claims.

Myoglianin acts on larval Drosophila neurons to induce the ecdysone receptor B1 isoform, which is essential for the metamorphic dismantling of the larval nervous system.

“One example, though, is the action of myoglianin on larval Drosophila neurons to induce the ecdysone receptor B1 isoform [2], which is essential for the metamorphic dismantling of the larval nervous system (reviewed in Ref. [61]).”

• cites [2] Awasaki, 2011, Glia instruct developmental neuronal remodeling through TGF-β signaling, Nat Neurosci sourceSupported
• cites [61] Truman, 2023, Drosophila postembryonic nervous system development: a model for the endocrine control of development, Genetics sourceSupported

May combine two claims.

In all three instances, Drosophila larvae progress through their three larval instars and then form a puparium.

“In all three instances, Drosophila larvae progress through their three larval instars and then form a puparium.”

• cites [41] Mirth, 2014, Juvenile hormone regulates body size and perturbs insulin signaling in Drosophila, Proc Natl Acad Sci USA sourcePartly supported

  The methods describe first-, second-, and third-instar Drosophila larvae and report checking L3 larvae for pupariation (Protein Starvation and Immunocytochemistry; Larval Weight and Pharate Adult Size Measurements; pages unavailable). This supports the developmental sequence, but the paper does not identify the “three instances” to which the citing sentence refers. (LLM, conf=0.78)

  Experimental — accuracy not yet measured
• cites [50] Riddiford, 2010, A role for juvenile hormone in the prepupal development of Drosophila melanogaster, Development sourcePartly supported

  The Discussion identifies the third instar as the last larval instar, and the Results report that the studied larvae survived through pupariation. This supports progression from the third instar to puparium formation, but the cited passages do not establish what the citing sentence’s “three instances” are or that the sequence occurred in all of them. (LLM, conf=0.78)

  Experimental — accuracy not yet measured
• cites [1] Abdou, 2011, Drosophila Met and Gce are partially redundant in transducing juvenile hormone action, Insect Biochem Mol Biol sourceNot checked — no full text of the source
• cites [49] Pecasse, 2000, Krüppel-homolog, a stage-specific modulator of the prepupal ecdysone response, is essential for Drosophila metamorphosis, Dev Biol sourcePartly supported

  The Introduction describes Drosophila larvae forming a puparium, and the Kr-h1 mutant section reports third-instar larvae that reach pupariation. Our copy does not identify the claim’s “three instances” or establish that larvae in all three progress through the larval instars and form a puparium. Page numbers were not available in the indexed passages. (LLM, conf=0.79)

  Experimental — accuracy not yet measured

May combine two claims.

When E93 was selectively knocked down in the pupal wing, the mutant region arrested development but also showed elevated and sustained expression of Broad.

“When E93 was selectively knocked down in the pupal wing, the mutant region arrested development but also showed elevated and sustained expression of Broad.”

• cites [11] Cruz, 2024, E93 controls adult differentiation by repressing broad in Drosophila, Proc Natl Acad Sci USA sourcePartly supported

  The Results section reports that selective E93 depletion in the wing caused significant impairment of terminal adult differentiation and persistently elevated Br during the pupal period. It also reports sustained high Br in specifically depleted wing compartments. It does not describe the mutant region as having arrested development; the depleted wings still developed, although with defects. (LLM, conf=0.83)

  Experimental — accuracy not yet measured

May combine two claims.

Knockdown of E93 allows persistence of Broad, thereby maintaining suppression of these genes.

“The knockdown of E93 allows the persistence of Broad, thereby maintaining suppression of these genes.”

• cites [11] Cruz, 2024, E93 controls adult differentiation by repressing broad in Drosophila, Proc Natl Acad Sci USA sourceSupported

May combine two claims.

Both Tribolium and Drosophila need JH and Kr-h1 to make the pupa.

“Although Tribolium and Drosophila differ in their need for JH to maintain their larval stage, both need JH and Kr-h1 to make the pupa (Figure 3b).”

• cites [64] Ureña, 2016, The occurrence of the holometabolous pupal stage requires the interaction between E93, Krüppel-homolog 1 and Broad-complex, PLoS Genet sourcePartly supported

  The Introduction reports that a prepupal Kr-h1 peak is critical for pupal formation in Tribolium and Drosophila. The Discussion does not establish that either species needs juvenile hormone (JH) to form a pupa: it calls JH control of the Tribolium peak plausible, notes that Drosophila Kr-h1 is also induced by 20E, and says the controlling factors remain unclear. Page numbers are not available in our copy. (LLM, conf=0.90)

  Experimental — accuracy not yet measured

May combine two claims.

These interventions severely disrupt prepupal development, and the insects die before head eversion.

“These interventions, though, severely disrupt prepupal development, and the insects die before head eversion.”

• cites [41] Mirth, 2014, Juvenile hormone regulates body size and perturbs insulin signaling in Drosophila, Proc Natl Acad Sci USA sourcePartly supported

  In “Ablation of the Corpora Allata” (page unavailable), the paper reports that only 5% of Aug21>rpr larvae eclosed as adults, supporting substantial failure to reach adulthood after that intervention. It does not say that prepupal development was severely disrupted or that the insects died before head eversion; some eclosed as adults. (LLM, conf=0.76)

  Experimental — accuracy not yet measured
• cites [50] Riddiford, 2010, A role for juvenile hormone in the prepupal development of Drosophila melanogaster, Development sourcePartly supported

  The Results report severely disrupted prepupal development: allatectomized larvae typically died around head eversion, and six of seven initiated it but could not complete it. This supports failure to complete head eversion in most animals, but not the claim that they died before head eversion began; one animal completed it. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites [1] Abdou, 2011, Drosophila Met and Gce are partially redundant in transducing juvenile hormone action, Insect Biochem Mol Biol sourceNot checked — no full text of the source
• cites [49] Pecasse, 2000, Krüppel-homolog, a stage-specific modulator of the prepupal ecdysone response, is essential for Drosophila metamorphosis, Dev Biol sourceSupported

May combine two claims.

Larvae lacking chinmo in Spodoptera frugiperda reach the L2 stage but die during the molt to the L3, with signs of premature metamorphosis.

“Larvae lacking chinmo reach the L2 stage but die during the molt to the L3, with signs of premature metamorphosis.”

• cites [10] Chen, 2024, Chronologically inappropriate morphogenesis (Chinmo) is required for maintenance of larval stages of fall armyworm., Proc Natl Acad Sci USA sourcePartly supported

  In Results and Discussion, the paper reports that Chinmo knockout fall armyworms developed normally until L2 and that most died during the molt to L3. It also reports premature expression of metamorphosis genes, but explicitly says that no obvious precocious metamorphosis phenotype was detected in Chinmo-only mutants; visible pupal patches were observed in the Chinmo/Kr-h1 double mutants instead. Page numbers are unavailable in our copy. (LLM, conf=0.89)

  Experimental — accuracy not yet measured

May combine two claims.

The JH decline evoked by crossing the threshold weight is sufficient to induce E93, but some other signal is needed for broad induction.

“Apparently, the JH decline evoked by crossing the threshold weight is sufficient to induce E93, but some other signal is needed for broad induction.”

• cites [9] Chafino, 2019, Upregulation of E93 gene expression acts as the trigger for metamorphosis independently of the threshold size in the beetle Tribolium castaneum, Cell Rep sourcePartly supported

  In “Size and Entry into Metamorphosis: A Trigger or an Association?” (page unavailable), the paper says JH decline activates TcE93 at later larval stages and proposes an additional competence factor governing when TcE93 can be induced. But it says threshold size is associated with JH decline, not that crossing the threshold causes it; the trigger of the normal JH decline remains unknown. It also does not characterize the additional factor as necessary specifically for “broad” induction. (LLM, conf=0.84)

  Experimental — accuracy not yet measured
• cites [8] Chafino, 2023, TGFß/activin-dependent activation of Torso controls the timing of the metamorphic transition in the red flour beetle Tribolium castaneum, PLoS Genet sourcePartly supported

  The Discussion (‘Up-regulation of Tc-torso depends on the TS checkpoint’; page unavailable) says that the JH decline at threshold size enables Tc-E93 up-regulation. The Results (‘The TGFß/Activin signaling pathway facilitates the metamorphic transition by regulating ecdysone levels’; page unavailable) show that suppressing JH alone did not promote metamorphosis and identify ecdysone as additionally required for the developmental transition. They do not establish that another signal is specifically needed for broad E93 induction. (LLM, conf=0.82)

  Experimental — accuracy not yet measured

May combine two claims.

As in Holometabola, E93 functions in hemimetabolous species to mediate the entry into metamorphosis, and its suppression results in permanent nymphs.

“As in the Holometabola, E93 functions in these species to mediate the entry into metamorphosis, and its suppression results in permanent nymphs [65,43].”

• cites [65] Ureña, 2014, Transcription factor E93 specifies adult metamorphosis in hemimetabolous and holometabolous insects, Proc Natl Acad Sci USA sourceNot checked — no full text of the source
• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourcePartly supported

  The Introduction identifies E93 as an adult-specifier gene in both hemimetabolous and holometabolous insects. The Results report that E93 knockdown alone produced an extra nymphal instar; the Discussion describes permanent nymphs only after E93 and chinmo were knocked down together. The claim omits that condition for the permanent-nymph outcome. Page numbers were not available in our copy. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

Allatectomized larvae of Bombyx mori form normal pupae, but they apparently still have prepupal JH from a source outside the corpora allata.

“Allatectomized larvae of Bombyx mori form normal pupae, but they apparently still have prepupal JH, which comes from a source outside of the corpora allata [29].”

• cites [29] Kayukawa, 2014, Hormonal regulation and developmental role of Krüppel homolog 1, a repressor of metamorphosis, in the silkworm Bombyx mori, Dev Biol sourceSupported

May combine two claims.

Broad appears not to suppress E93 expression in larvae of Tribolium, although it does in larvae of Spodoptera frugiperda.

“Broad appears not to suppress E93 expression in larvae of Tribolium [64], although it does in larvae of Spodoptera frugiperda [36].”

• cites [64] Ureña, 2016, The occurrence of the holometabolous pupal stage requires the interaction between E93, Krüppel-homolog 1 and Broad-complex, PLoS Genet sourceSupported
• cites [36] Liu, 2025, Knockout BR-C induces premature expression of E93 thus triggering adult differentiation under larval morphology, Pest Manag Sci sourceSupported

May combine two claims.

Myoglianin evokes premetamorphic changes in hemimetabolous insects and suppresses the corpora allata, causing a JH decline, and potentiates prothoracic gland activity.

“Myoglianin also evokes premetamorphic changes in hemimetabolous insects and is especially prominent in the endocrine system, where it suppresses the corpora allata, causing a JH decline [25,22], and potentiates prothoracic gland activity [25].”

• cites [25] Kamsoi, 2019, Myoglianin triggers the premetamorphosis stage in hemimetabolan insects, FASEB J sourcePartly supported

  The Abstract reports that Myoglianin represses a juvenile-hormone biosynthesis gene in the corpora allata and stimulates ecdysone-biosynthesis genes in the prothoracic glands. It concludes that Myoglianin triggers the premetamorphic stage in Blattella germanica, but says this is only possible in other hemimetabolan insects; the claim presents that broader effect without the qualifier. (LLM, conf=0.85)

  Experimental — accuracy not yet measured
• cites [22] Ishimaru, 2016, TGF-beta signaling in insects regulates metamorphosis via juvenile hormone biosynthesis, Proc Natl Acad Sci USA sourcePartly supported

  The paper reports that Myoglianin suppresses JH biosynthesis in the corpora allata of the hemimetabolous cricket Gryllus bimaculatus and that its loss prevents metamorphosis. But the Additional information section says no connection between Myoglianin and ecdysone biosynthesis was established in this study; expression in the prothoracic gland does not show that it potentiates the gland's activity. Page numbers are unavailable in our copy. (LLM, conf=0.90)

  Experimental — accuracy not yet measured

May combine two claims.

Chinmo maintains the larval state in both Drosophila and Tribolium, and it inhibits both broad and E93 expression.

“Chinmo maintains the larval state in both Drosophila [59,7] and Tribolium [30], and it inhibits both broad and E93 expression .”

• cites [59] Truman, 2022, Chinmo is the larval member of the molecular trinity that directs Drosophila metamorphosis., Proc Natl Acad Sci USA sourceSupported
• cites [7] Chafino, 2023, Antagonistic role of the BTB-zinc finger transcription factors Chinmo and Broad-complex in the juvenile/pupal transition and in growth control, eLife sourceSupported
• cites [30] Khong, 2024, The BTB transcription factor, abrupt, acts cooperatively with chronologically inappropriate morphogenesis (Chinmo) to repress metamorphosis and promotes leg regeneration, Dev Biol sourceNot checked — no full text of the source

May combine two claims.

Proper broad induction in Drosophila wing discs at pupariation requires Kr-h1, which prevents precocious expression of E93 and suppression of broad expression.

“For example, proper broad induction in Drosophila wing discs at pupariation requires Kr-h1, which prevents precocious expression of E93 and suppression of broad expression [64].”

• cites [64] Ureña, 2016, The occurrence of the holometabolous pupal stage requires the interaction between E93, Krüppel-homolog 1 and Broad-complex, PLoS Genet sourceSupported

May combine two claims.

In late Drosophila larvae, Kr-h1 expression comes under control of ecdysteroids, so ecdysteroids may substitute for a lack of JH.

“In late Drosophila larvae , by contrast, Kr-h1 expression comes under control of ecdysteroids [37], so the latter may substitute for a lack of JH.”

• cites [37] Long, 2025, 20E-induced Kr-h1 expression facilitates developmental transitions depending on chromosome accessibility of BR-C enhancers, Proc Natl Acad Sci USA sourceSupported

May combine two claims.

Hemimetabolous nymphal growth combines growth with differentiation, while during larval growth in holometabolous insects these components are separated, with an initial growth phase followed by a phase of determination.

“Manthey et al. [38] conclude that hemimetabolous nymphal growth combines growth with differentiation, while during larval growth in holometabolous insects, these components are separated with an initial growth phase, followed by a phase of determination.”

• cites [38] Manthey, 2024, Rapid growth and the evolution of complete metamorphosis in insects, Proc Natl Acad Sci USA sourcePartly supported

  The Abstract says hemimetabolous nymphs grow and differentiate throughout development, whereas holometabolous insects grow chiefly as larvae and differentiate adult organs chiefly as pupae. The Methods (Model Description) likewise describes a growth phase followed by a phase of differentiation—not a phase of determination during larval growth. (LLM, conf=0.85)

  Experimental — accuracy not yet measured

May combine two claims.

In the hemimetabolous bug, chinmo and broad are expressed simultaneously and collaborate to support the positive allometric growth of the wing pads.

“In the bug, the two genes are expressed simultaneously and collaborate to support the positive allometric growth of the wing pads.”

• cites [16] Erezyilmaz, 2006, The pupal specifier broad directs progressive morphogenesis in a direct-developing insect., Proc Natl Acad Sci USA sourcePartly supported

  The Results (page not provided) show that broad is critical for anisometric wing-pad growth in the milkweed bug: knocking it down reduces that growth. Neither the supplied passages nor a search of our copy for chinmo supports simultaneous expression of chinmo and broad or collaboration between them. (LLM, conf=0.89)

  Experimental — accuracy not yet measured
• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourcePartly supported

  The Introduction and the Discussion section ‘chinmo and br are co-expressed during the nymphal stage’ support simultaneous expression in O. fasciatus nymphs. But the Discussion section ‘Chinmo regulates isometric growth and nymphal morphogenesis’ says the genes act antagonistically: Br promotes allometric wing growth, whereas Chinmo favors isometric growth. It does not support the claim that they collaborate to promote positive allometric wing-pad growth. (LLM, conf=0.88)

  Experimental — accuracy not yet measured

May combine two claims.

In the Drosophila wing disc, Chinmo acting alone directs a self-regenerative, isomorphic growth of the disc, and then Broad supports determinative changes that transform the simple epithelium into the patterned pupal appendage.

“In the Drosophila wing disc, in contrast, Chinmo, acting alone, directs a self-regenerative, isomorphic growth of the disc, and then Broad supports determinative changes that transform the simple epithelium into the patterned pupal appendage [45].”

• cites [45] Narbonne-Reveau, 2019, Developmental regulation of regenerative potential in Drosophila by ecdysone through a bistable loop of ZBTB transcription factors., PLoS Biol sourcePartly supported

  The Results say Chinmo promotes an undifferentiated, self-renewing state and is required for efficient wing-disc regeneration; the Discussion says Br helps initiate differentiation. But the paper does not establish that Chinmo acts alone or that growth is isomorphic. It describes other signaling pathways in regeneration and says Br cooperates with ecdysone signaling in differentiation; it does not specifically attribute transformation into a patterned pupal appendage to Br. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

Although chinmo and broad work in concert to direct the progressive growth of the nymph, only chinmo is involved in the regulation of E93.

“Although chinmo and broad work in concert to direct the progressive growth of the nymph, only chinmo is involved in the regulation of E93 [44,43].”

• cites [44] Nagata, 2026, Evolution and development of insect metamorphosis: a case of genetic accommodation?, Results Probl CellDiffer sourceNot checked — no full text of the source
• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourceSupported

May combine two claims.

In holometabolous insects the expression of chinmo and broad is separated, with Chinmo directing the early proliferative expansion of the primordium, followed by Broad directing its morphogenesis into a pupal wing.

“The expression of these two genes is separated in the holometabolous insects, with Chinmo directing the early proliferative expansion of the primordium, followed by Broad directing its morphogenesis into a pupal wing.”

• cites [16] Erezyilmaz, 2006, The pupal specifier broad directs progressive morphogenesis in a direct-developing insect., Proc Natl Acad Sci USA sourcePartly supported

  The Abstract and Discussion describe Broad expression at the larval–pupal transition and its role in morphogenesis in holometabolous insects. Our copy does not mention Chinmo or establish that Chinmo first drives proliferative expansion of a wing primordium, so it does not support the proposed sequence of the two genes. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourcePartly supported

  The Discussion (‘Implications for the evolution of metamorphosis’; page unavailable) describes temporally separated roles in holometabolous insects: Chinmo regulates early imaginal-disc growth, followed by Broad promoting differentiation. It does not specifically establish proliferative expansion of a wing primordium or its morphogenesis into a pupal wing, and frames the evolutionary separation of these roles as a possibility. (LLM, conf=0.82)

  Experimental — accuracy not yet measured

May combine two claims.

Lack of chinmo results in accelerated change and premature E93 expression and metamorphosis.

“while lack of chinmo results in accelerated change and premature E93 ex­ pression and metamorphosis.”

• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourceSupported

The quote only partly states this claim.

Precocious 'last stage' nymphs lacking both chinmo and E93 continue to molt to additional last stage nymphs.

“In such cases, precocious 'last stage' nymphs continue to molt to additional last stage nymphs due to a lack of E93.”

• cites [43] Nagata, 2026, Evolution of complete metamorphosis through temporal shifts in Cronologically inappropriate morphogenesis (Chinmo) and Broad, Development sourcePartly supported

  The Results section ('E93 but not br is upregulated in chinmo knockdown nymphs'; page unavailable) reports that nymphs with both chinmo and E93 knocked down molted into another nymph rather than a precocious adult. It does not establish that these were 'last stage' nymphs or that they continued through multiple additional nymphal molts. (LLM, conf=0.82)

  Experimental — accuracy not yet measured

May combine two claims.

Krüppel-homolog 1 (Kr-h1) suppresses metamorphosis and maintains the larval stage.

“The JH target gene Krüppel-homolog 1 ( Kr-h1 ) also suppresses metamorphosis, but the need for JH in maintaining the larva varies.”

• Also stated in: § The metamorphic gene network · p. 2 · plain

  “Kr-h1 is involved in maintaining the larval stage.”

• cites [23] Jindra, 2015, Molecular basis of juvenile hormone signaling, Curr Opin Insect Sci sourceNot checked — no full text of the source
• cites [24] Jindra, 2013, The juvenile hormone signaling pathway in insect development, Annu Rev Entomol sourceNot checked — no full text of the source

May combine two claims.

Ectopic expression of broad in second instar larvae results in expression of pupal rather than larval cuticle genes, whereas expression in the pupal stage suppresses adult morphogenesis and induces expression of pupal rather than adult cuticle genes.

“Ectopic expression of broad in second instar larvae results in expression of pupal rather than larval cuticle genes, whereas expression in the pupal stage suppresses adult morphogenesis and induces expression of pupal rather than adult cuticle genes [69].”

• cites [69] Zhou, 2002, Broad specifies pupal development and mediates the ‘status quo’ action of juvenile hormone on the pupal-adult transformation in Drosophila and Manduca, Development sourceNot checked — no full text of the source

The quote only partly states this claim.

Kr-h1 mediates the anti-metamorphic action of juvenile hormone (JH).

“JH acting through its receptor complex of Met/taiman (Methoprene tolerant/taiman) induces expression of Krh1.”

• cites [23] Jindra, 2015, Molecular basis of juvenile hormone signaling, Curr Opin Insect Sci sourceNot checked — no full text of the source
• cites [24] Jindra, 2013, The juvenile hormone signaling pathway in insect development, Annu Rev Entomol sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing).

The cells of the eye primordium are determined during embryogenesis.

“The cells of the primordium are determined during embryogenesis.”

May combine two claims.

Invaginated wing discs do not make larval cuticle and divide through both molt and intermolt phases.

“By contrast, invaginated wing discs do not make larval cuticle and divide through both molt and intermolt phases [54].”

• cites [54] S̆vácha, 1992, What are and what are not imaginal discs: reevaluation of some basic concepts (Insecta, Holometabola), Dev Biol sourceNot checked — no full text of the source

May combine two claims.

Kr-h1 transcripts track JH levels through larval life, and knockdown of Kr-h1 levels mimics JH loss.

“Kr-h1 transcripts track JH levels through larval life, and knockdown of Kr-h1 levels mimics JH loss [23,24].”

• cites [23] Jindra, 2015, Molecular basis of juvenile hormone signaling, Curr Opin Insect Sci sourceNot checked — no full text of the source
• cites [24] Jindra, 2013, The juvenile hormone signaling pathway in insect development, Annu Rev Entomol sourceNot checked — no full text of the source

May combine two claims.

JH transiently reappears during the prepupal stage, where it is primarily needed by the imaginal discs and primordia.

“JH transiently reappears during the prepupal stage, where it is primarily needed by the imaginal discs and primordia.”

• cites [66] Williams, 1961, The juvenile hormone. II. Its role in the endocrine control of molting, pupation, and adult development of the cecropia silkworm, Biol Bull sourceNot checked — no full text of the source

May combine two claims.

Deletion of both JH receptors results in normal larval progression but delayed pupariation.

“The normal larval progression is also seen after deletion of both JH receptors, but pupariation is also delayed [1].”

• cites [1] Abdou, 2011, Drosophila Met and Gce are partially redundant in transducing juvenile hormone action, Insect Biochem Mol Biol sourceNot checked — no full text of the source

May combine two claims.

The eye primordium makes a head capsule cuticle during most of larval life, but remains diploid and has the capacity to become an eye imaginal disc.

“They make a head capsule cuticle during most of larval life, but remain diploid and have the capacity to become an eye imaginal disc.”

May combine two claims.

When Broad appears early in the last instar, the eye primordium detaches from the head capsule cuticle and begins morphogenetic growth.

“When Broad appears early in the last instar, the eye primordium detaches from the head capsule cuticle and begins morphogenetic growth [56].”

• cites [56] Truman, 2006, Juvenile hormone is required to couple imaginal disc formation with nutrition in insects, Science sourceNot checked — no full text of the source

May combine two claims.

Knockdown of abrupt alone did not induce precocious metamorphosis nor alter levels of broad, E93, or Kr-h1.

“The knockdown of abrupt alone, though, did not induce precocious metamorphosis nor did it alter levels of broad , E93 , or Kr-h1.”

• cites [30] Khong, 2024, The BTB transcription factor, abrupt, acts cooperatively with chronologically inappropriate morphogenesis (Chinmo) to repress metamorphosis and promotes leg regeneration, Dev Biol sourceNot checked — no full text of the source

May combine two claims.

Higher flies have only three larval instars and are still in their JH-insensitive phase when they commit to metamorphosis.

“The latter insects have only three larval instars and are still in their JH-insensitive phase when they commit to metamorphosis.”

May combine two claims.

The cells of the eye imaginal primordium become determined progressively so that by the prepupal ecdysteroid peak, disc cells posterior to the morphogenetic furrow have acquired determined fates, while those anterior remain undetermined.

“The cells of the eye imaginal primordium become determined progressively so that by the time of the prepupal ecdysteroid peak, the disc cells posterior to the morphogenetic furrow have acquired determined fates, while those anterior to the furrow remain undetermined.”

May combine two claims.

Extensive cross-inhibition amongst Chinmo, broad, and E93 maintains stage stability, but the endocrine landscape disrupts the status quo and allows transition from one stage to the next.

“Extensive cross-inhibition amongst these genes maintains stage stability, but the endocrine landscape, working through JH, ecdysone, and other prometamorphic factors, disrupts the status quo and allows transition from one stage to the next.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Hemimetabolous development appeared after the evolution of wings.

“The first type of metamorphic development (hemimetabolous development) appeared after the evolution of wings [42].”

• cites [42] Misof, 2014, Phylogenomics resolves the timing and pattern of insect evolution, Science sourceNot checked — no full text of the source

May combine two claims.

The uncoupling of larval and adult body plans allowed the optimization of the larva for feeding and growth, while the adult was optimized for flight and reproduction.

“This uncoupling allowed the optimization of the larva for feeding and growth, while the adult was optimized for flight and reproduction.”

May combine two claims.

Inhibitory interactions between broad and E93, and a return of JH in the prepupa, ensure that Broad and pupa formation occur before E93 and adult differentiation.

“Inhibitory interactions between broad and E93, and a return of JH in the prepupa, ensure that Broad and pupa formation occur before E93 and adult differentiation.”

• Also stated in: § The endocrine landscape for growth and metamorphosis · p. 4 · plain

  “JH transiently reappears during the prepupal stage, where it is primarily needed by the imaginal discs and primordia. In its absence, some primordia undergo adult, rather than pupal differentiation [66].”

• cites [66] Williams, 1961, The juvenile hormone. II. Its role in the endocrine control of molting, pupation, and adult development of the cecropia silkworm, Biol Bull sourceNot checked — no full text of the source

May combine two claims.

While JH and Kr-h1 are present in larval Drosophila, their presence or absence does not affect larval life, suggesting that they are not needed to maintain Chinmo.

“While JH and Kr-h1 are present in larval Drosophila, their presence or absence does not affect larval life, suggesting that they are not needed to maintain Chinmo.”

May combine two claims.

JH is not needed for progression through the larval stages, but it is essential during the prepupal period.

“Thus, JH is not needed for the progression through the larval stages, but it is essential during the prepupal period.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The state of cell determination in the imaginal primordia during pupa formation may vary amongst species, and this might influence how they respond to JH removal.

“Also, as noted above, the state of cell determination in the imaginal primordia during pupa formation may vary amongst species, and this might influence how they respond to JH removal.”

May combine two claims.

In the absence of Broad, growth occurs but without progressive developmental change.

“Thus, in the absence of Broad, growth occurs but without progressive developmental change.”