CoChat
Sign Up
Cited by 18Neurobiology and Insect Physiology ResearchDevelopmental Biology and Gene RegulationGenomics and Chromatin Dynamics

Chronologically inappropriate morphogenesis ( Chinmo ) is required for maintenance of larval stages of fall armyworm

Open access
Chen, Xien, Koo, Jinmo, Kumar Arya, Surjeet, Palli, Subba Reddy·2024·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.2411286121PMC PMC11626174
Open this paper in CoChat — free accountOpen PDF

Abstract

Broad complex (Br-C) and eip93F (E93) transcription factors promote insect metamorphosis from larva to pupa and from pupa to adult, respectively. Recently, chronologically inappropriate morphogenesis (Chinmo) has been proposed as a larval specifier in Drosophila melanogaste r. However, whether Chinmo is required for larval maintenance in lepidopteran insects, the underlying mechanisms involved in maintaining the larval stage, and its interactions with the JH signaling pathway are not well understood. Here, we used a binary transgenic CRISPR/Cas9 system to knockout Chinmo and Kr-h1 (primary response gene in the JH signaling pathway) in the fall armyworm (FAW). Kr-h1 knockout induced premature metamorphosis only after L5 (penultimate), whereas Chinmo and Kr-h1 double knockout induced premature metamorphosis in L3. Sequencing and differential gene expression (DEG) analysis of RNA isolated from mutants and single-cell multiome ATAC analysis of Chinmo , Kr-h1 , and Chinmo and Kr-h1 double knockout Sf9 cells revealed that Chinmo participates in chromatin modifications that prevent the promoter accessibility and expression of metamorphosis promoting genes. These results suggest that Chinmo is a larval specifier that plays a major role in preventing metamorphosis in early larval stages by controlling chromatin accessibility near the promoters of genes such as Br-C and E93 required for pupal and adult development.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1073/pnas.2411286121

Cites

2 of 2 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Double knockouts of both chinmo and Kr-h1 do not differ significantly from the knockout of chinmo alone.

    “Double knockouts of both chinmo and Kr-h1 do not differ significantly from the knockout of chinmo alone.”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [10]

    In Results and Discussion, the paper reports that the double knockout, unlike the chinmo-only knockout, showed cuticle melanization and pupal patches. It also reports greater upregulation of metamorphosis-related genes in the double mutant. Although most larvae in both groups died during the L3 molt, the paper does not support the unqualified claim that the knockouts do not differ significantly. Page numbers were not supplied. (LLM, conf=0.88)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

  • 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.”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [10]

    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

  • Larvae lacking Kr-h1 in Spodoptera frugiperda are not affected until the molt to the L5 (penultimate) instar.

    “By contrast, those lacking Kr-h1 are not affected until the molt to the L5 (penultimate) instar.”

    From Regulation of metamorphosis in holometabolous insects (2026) · cites this paper as [10]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 56

  1. [1]L. M. Riddiford, Rhodnius, golden oil, and Met: A history of juvenile hormone research. Front. Cell Dev. Biol. 8, 679 (2020). 32850806 PMC7426621
  2. [2]X. Pan, R. P. Connacher, M. B. O’Connor, Control of the insect metamorphic transition by ecdysteroid production and secretion. Curr. Opin. Insect Sci. 43, 11– 20 (2021). 32950745 PMC7965781
  3. [3]K. Hiruma, Y. Kaneko, Hormonal regulation of insect metamorphosis with special reference to juvenile hormone biosynthesis. Curr. Topics Dev. Biol. 103, 73– 100 (2013). 23347516
  4. [4]M. Jindra, S. R. Palli, L. M. Riddiford, The juvenile hormone signaling pathway in insect development. Ann. Rev. Entomol. 58, 181– 204 (2013). 22994547
  5. [5]T. Kayukawa, A. Jouraku, Y. Ito, T. Shinoda, Molecular mechanism underlying juvenile hormone-mediated repression of precocious larval-adult metamorphosis. Proc. Natl. Acad. Sci. U.S.A. 114, 1057– 1062 (2017). 28096379 PMC5293048
  6. [6]T. Kayukawa, Krüppel homolog 1 inhibits insect metamorphosis via direct transcriptional repression of Broad-complex, a pupal specifier gene. J. Biol. Chem. 291, 1751– 1762 (2016). 26518872 PMC4722455
  7. [7]B. Konopova, M. Jindra, Juvenile hormone resistance gene Methoprene-tolerant controls entry into metamorphosis in the beetle Tribolium castaneum. Proc. Natl. Acad. Sci. U.S.A. 104, 10488– 10493 (2007). 17537916 PMC1965540
  8. [8]B. Konopova, V. Smykal, M. Jindra, Common and distinct roles of juvenile hormone signaling genes in metamorphosis of holometabolous and hemimetabolous insects. PloS one 6, e28728 (2011). 22174880 PMC3234286
  9. [9]C. Minakuchi, T. Namiki, T. Shinoda, Krüppel homolog 1, an early juvenile hormone-response gene downstream of Methoprene-tolerant, mediates its anti-metamorphic action in the red flour beetle Tribolium castaneum. Dev. Biol. 325, 341– 350 (2009). 19013451
  10. [10]T. Daimon, M. Uchibori, H. Nakao, H. Sezutsu, T. Shinoda, Knockout silkworms reveal a dispensable role for juvenile hormones in holometabolous life cycle. Proc. Natl. Acad. Sci. U.S.A. 112, E4226– E4235 (2015). 26195792 PMC4534237
  11. [11]V. Smykal, Importance of juvenile hormone signaling arises with competence of insect larvae to metamorphose. Dev. Biol. 390, 221– 230 (2014). 24662045
  12. [12]D. Martín, S. Chafino, X. Franch-Marro, How stage identity is established in insects: The role of the metamorphic gene network. Curr. Opin. Insect Sci. 43, 29– 38 (2021). 33075581
  13. [14]C. Dillard, K. Narbonne-Reveau, S. Foppolo, E. Lanet, C. Maurange, Two distinct mechanisms silence chinmo in Drosophila neuroblasts and neuroepithelial cells to limit their self-renewal. Development 145, dev154534 (2018). 29361557
  14. [15]S. Zhu, Gradients of the Drosophila Chinmo BTB-zinc finger protein govern neuronal temporal identity. Cell 127, 409– 422 (2006). 17055440
  15. [16]M. H. Syed, B. Mark, C. Q. Doe, Steroid hormone induction of temporal gene expression in Drosophila brain neuroblasts generates neuronal and glial diversity. Elife 6, e26287 (2017). 28394252 PMC5403213
  16. [17]K. Doggett, BTB-zinc finger oncogenes are required for Ras and Notch-driven tumorigenesis in Drosophila. PLoS One 10, e0132987 (2015). 26207831 PMC4514741
  17. [18]K. Narbonne-Reveau, C. Maurange, Developmental regulation of regenerative potential in Drosophila by ecdysone through a bistable loop of ZBTB transcription factors. PLoS Biol. 17, e3000149 (2019). 30742616 PMC6386533
  18. [20]L. M. Riddiford, M. Ashburner, Effects of juvenile hormone mimics on larval development and metamorphosis of Drosophila melanogaster. Gen. Comp. Endocrinol. 82, 172– 183 (1991). 1906823
  19. [21]X. Chen, S. R. Palli, Hyperactive piggyBac transposase-mediated germline transformation in the fall armyworm, Spodoptera frugiperda. JoVE 175, e62714 (2021). 34633386
  20. [23]J. Chang, Genome-wide CRISPR screening reveals genes essential for cell viability and resistance to abiotic and biotic stresses in Bombyx mori. Genome Res. 30, 757– 767 (2020). 32424075 PMC7263191
  21. [24]T. Kayukawa, Hormonal regulation and developmental role of Krüppel homolog 1, a repressor of metamorphosis, in the silkworm Bombyx mori. Dev. Biol. 388, 48– 56 (2014). 24508345
  22. [25]E. Ureña, S. Chafino, C. Manjón, X. Franch-Marro, D. Martín, The occurrence of the holometabolous pupal stage requires the interaction between E93, Krüppel-Homolog 1 and Broad-Complex. PLoS Genet. 12, e1006020 (2016). 27135810 PMC4852927
  23. [26]H. Mabashi-Asazuma, D. L. Jarvis, CRISPR-Cas9 vectors for genome editing and host engineering in the baculovirus–insect cell system. Proc. Natl. Acad. Sci. U.S.A. 114, 9068– 9073 (2017). 28784806 PMC5576809
  24. [28]G. H. Zhu, Y. Jiao, S. Chereddy, M. Y. Noh, S. R. Palli, Knockout of juvenile hormone receptor, Methoprene-tolerant, induces black larval phenotype in the yellow fever mosquito, Aedes aegypti. Proc. Natl. Acad. Sci. U.S.A. 116, 21501– 21507 (2019). 31570611 PMC6815201
  25. [29]H. Bai, P. Ramaseshadri, S. R. Palli, Identification and characterization of juvenile hormone esterase gene from the yellow fever mosquito, Aedes aegypti. Insect Biochem. Mol. Biol. 37, 829– 837 (2007). 17628281 PMC2020842
  26. [30]A. Tan, H. Tanaka, T. Tamura, T. Shiotsuki, Precocious metamorphosis in transgenic silkworms overexpressing juvenile hormone esterase. Proc. Natl. Acad. Sci. U.S.A. 102, 11751– 11756 (2005). 16087883 PMC1187958
  27. [31]Z. Zhang, Depletion of juvenile hormone esterase extends larval growth in Bombyx mori. Insect Biochem. Mol. Biol. 81, 72– 79 (2017). 28057597
  28. [33]K. Hiruma, L. M. Riddiford, The molecular mechanisms of cuticular melanization: The ecdysone cascade leading to dopa decarboxylase expression in Manduca sexta. Insect Biochem. Mol. Biol. 39, 245– 253 (2009). 19552890
  29. [34]T. Shinoda, K. Itoyama, Juvenile hormone acid methyltransferase: A key regulatory enzyme for insect metamorphosis. Proc. Natl. Acad. Sci. U.S.A. 100, 11986– 11991 (2003). 14530389 PMC218700
  30. [35]F. G. Noriega, Juvenile hormone biosynthesis in insects: What is new, What do we know, and What questions remain? Int. Sch. Res. Notices 2014, 967361 (2014). 27382622 PMC4897325
  31. [36]M. Hejnikova, M. Paroulek, M. Hodkova, Decrease in Methoprene tolerant and Taiman expression reduces juvenile hormone effects and enhances the levels of juvenile hormone circulating in males of the linden bug Pyrrhocoris apterus. J. Insect Physiol. 93, 72– 80 (2016). 27570150
  32. [37]M. Gijbels, C. Lenaerts, J. Vanden Broeck, E. Marchal, Juvenile Hormone receptor Met is essential for ovarian maturation in the Desert Locust, Schistocerca gregaria. Sci. Rep. 9, 10797 (2019). 31346226 PMC6658565
  33. [38]J. Leyria, I. Orchard, A. B. Lange, Impact of JH signaling on reproductive physiology of the classical insect model, Rhodnius prolixus. Int. J. Mol. Sci. 23, 13832 (2022). 36430311 PMC9692686
  34. [39]Y. Obara, Pupal commitment and its hormonal control in wing imaginal discs. J. Insect Physiol. 48, 933– 944 (2002). 12770040
  35. [40]G. Jones, N. Brown, M. Manczak, S. Hiremath, F. C. Kafatos, Molecular cloning, regulation, and complete sequence of a hemocyanin-related, juvenile hormone-suppressible protein from insect hemolymph. J. Biol. Chem. 265, 8596– 8602 (1990). 2341396
  36. [41]G. Jones, M. Wozniak, D. Jones, Newly identified, basic hemolymph proteins from noctuid species. Biochem. Biophys. Res. Commun. 146, 265– 269 (1987). 3606619
  37. [42]V. Exner, P. Taranto, N. Schönrock, W. Gruissem, L. Hennig, Chromatin assembly factor CAF-1 is required for cellular differentiation during plant development. Development (Cambridge, England) 133, 4163– 4172 (2006). 17021044
  38. [43]M. Clémot, A. Molla-Herman, J. Mathieu, J. R. Huynh, N. Dostatni, The replicative histone chaperone CAF1 is essential for the maintenance of identity and genome integrity in adult stem cells. Development (Cambridge, England) 145, dev161190 (2018). 30093554
  39. [44]A. Auger, Eaf1 is the platform for NuA4 molecular assembly that evolutionarily links chromatin acetylation to ATP-dependent exchange of histone H2A variants. Mol. Cell Biol. 28, 2257– 2270 (2008). 18212047 PMC2268442
  40. [45]R. Parthasarathy, S. R. Palli, Stage-specific action of juvenile hormone analogs. J. Pestic. Sci. 46, 16– 22 (2021). 33746542 PMC7953018
  41. [46]M. Kamimura, M. Kiuchi, Applying fenoxycarb at the penultimate instar triggers an additional ecdysteroid surge and induces perfect extra larval molting in the silkworm. Gen. Comp. Endocrinol. 128, 231– 237 (2002). 12392697
  42. [47]H. Khong, K. B. Hattley, Y. Suzuki, The BTB transcription factor, Abrupt, acts cooperatively with Chronologically inappropriate morphogenesis (Chinmo) to repress metamorphosis and promotes leg regeneration. Dev. Biol. 509, 70– 84 (2024). 38373692
  43. [48]Q. He, Y. Zhang, Kr-h1, a cornerstone gene in insect life history. Front. Physiol. 13, 905441 (2022). 35574485 PMC9092015
  44. [49]M. J. Niederhuber, D. J. McKay, Mechanisms underlying the control of dynamic regulatory element activity and chromatin accessibility during metamorphosis. Curr. Opin. Insect Sci. 43, 21– 28 (2021). 32979530 PMC7985040
  45. [50]C. M. Uyehara, Hormone-dependent control of developmental timing through regulation of chromatin accessibility. Genes Dev. 31, 862– 875 (2017). 28536147 PMC5458754
  46. [51]S. L. Nystrom, M. J. Niederhuber, D. J. McKay, Expression of E93 provides an instructive cue to control dynamic enhancer activity and chromatin accessibility during development. Development (Cambridge, England) 147, dev181909 (2020). 32094114 PMC7097197
  47. [53]X. Chen, S. Chereddy, D. Gurusamy, S. R. Palli, Identification and characterization of highly active promoters from the fall armyworm, Spodoptera frugiperda. Insect Biochem. Mol. Biol. 126, 103455 (2020). 32827641
  48. [54]A. Roy, S. R. Palli, Epigenetic modifications acetylation and deacetylation play important roles in juvenile hormone action. BMC Genomics 19, 934 (2018). 30547764 PMC6295036
  49. [55]X. Chen, J. Koo, S. K. Arya, S. R. Palli, Data from “Chronologically inappropriate morphogenesis (Chinmo) is required for maintenance of larval stages of fall armyworm.” NCBI. https://dataview.ncbi.nlm.nih.gov/object/PRJNA1168504. Deposited 3 October 2024. PMC11626174 39589873
  50. [57]X. Chen, J. Koo, S. K. Arya, S. R. Palli, Data from “Chronologically inappropriate morphogenesis (Chinmo) is required for maintenance of larval stages of fall armyworm.” NCBI. https://dataview.ncbi.nlm.nih.gov/object/PRJNA1168511. Deposited 3 October 2024. PMC11626174 39589873
  51. [58]T. Stuart, A. Srivastava, S. Madad, C. A. Lareau, R. Satija, Single-cell chromatin state analysis with Signac. Nat. Methods 18, 1333– 1341 (2021). 34725479 PMC9255697
  52. [59]J. M. Gaspar, Improved peak-calling with MACS2. bioXriv [Preprint] (2018). 10.1101/496521 (Accessed 17 December 2018). · DOI
  53. [60]A. Khan, JASPAR 2018: Update of the open-access database of transcription factor binding profiles and its web framework. Nucleic Acids Res. 46, D1284 (2018). 29161433 PMC5753202
  54. [61]W. Huber, Orchestrating high-throughput genomic analysis with Bioconductor. Nat. Methods 12, 115– 121 (2015). 25633503 PMC4509590
  55. [62]R. C. Gentleman, Bioconductor: Open software development for computational biology and bioinformatics. Genome Biol. 5, R80 (2004). 15461798 PMC545600
  56. [63]T. L. Bailey, MEME SUITE: Tools for motif discovery and searching. Nucleic Acids Res. 37, W202– 208 (2009). 19458158 PMC2703892

Cited by

Sorted by citations

Authors
Chen, X., Koo, J., Kumar Arya, S., & Palli, S. R.
Affiliations
  • University of Kentucky (US)
  • Department of Entomology, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546
Corresponding author
  • Chen, Xien
  • Koo, Jinmo
  • Palli, Subba Reddy
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2024-11-26
Volume
121
Issue
49
Pages
e2411286121-e2411286121
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.2411286121
PMC
PMC11626174
OpenAlex
W4404742439
Cited by
18
References
2
Citations by year
2026: 11 · 2025: 6 · 2024: 1
FWCI
3.15
Type
journal article
Language
en
Open access
Licence
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • UKnowledge (University of Kentucky) (submittedVersion, cc-by-nc-nd)
Funders
U.S. Department of Agriculture (2019-67013-29351, 2353057000)
Topics
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurobiology and Insect Physiology Research
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Developmental Biology and Gene Regulation
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Genomics and Chromatin Dynamics
Keywords
Chinmo, Kr-h1, Spodoptera frugiperda, metamorphosis, juvenile hormone signaling, chromatin accessibility, promoter accessibility, Broad-Complex, CRISPR/Cas9 knockout
MeSH terms
Animals, Drosophila melanogaster, Larva, Metamorphosis, Biological, Morphogenesis, Pupa, Transcription Factors, Signal Transduction, Gene Expression Regulation, Developmental, Drosophila Proteins, Kruppel-Like Transcription Factors, CRISPR-Cas Systems

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review