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Cited by 6Lipid metabolism and biosynthesisCancer, Lipids, and MetabolismSphingolipid Metabolism and Signaling

The DOI matches its Crossref record; 40 of the 40 references it cites were found in a registry or an index; 12 of the 18 sources its claims cite were checked for support.

Molecular insights into human phosphatidylserine synthase 2 and its regulation of SREBP pathways

Open access
Li, Dongyu, Chen, Hongwen, Vale, Goncalo, Elghobashi-Meinhardt, Nadia, Hatton, Alexandra, Rong, Shunxing, McDonald, Jeffrey G., Li, Xiaochun·2025·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.2501177122PMC PMC12107096
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Abstract

Homologous proteins share similar sequences, enabling them to work together in cells to support normal physiological functions. Phosphatidylserine synthases 1 and 2 (PSS1 and PSS2) are homologous enzymes that catalyze the synthesis of phosphatidylserine (PS) from different substrates. PSS2 shows a preference for phosphatidylethanolamine (PE) as its substrate, whereas PSS1 can utilize either PE or phosphatidylcholine. Previous studies showed that inhibiting PSS1 promotes SREBP-2 cleavage. Interestingly, despite their homology, our findings reveal that PSS2 exerts an opposing effect on the cleavage of both SREBP-1 and SREBP-2. We resolved the cryo-electron microscopy (cryo-EM) structure of human PSS2 at 3.3 Å resolution. Structural comparison of the catalytic cavities between PSS1 and PSS2 along with molecular dynamics simulations uncovers the molecular details behind the substrate preference of PSS2 for PE. The lipidomic analysis showed that PSS2 deficiency leads to PE accumulation in the endoplasmic reticulum, which has been shown to inhibit the cleavage of sterol regulatory element-binding proteins (SREBPs) in mice. Thus, our findings reveal the intricate network of intracellular phospholipid metabolism and underscore the distinct regulatory roles of homologous proteins in cellular activities.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

PSS2 deficiency in CHO-K1 cells suppresses SREBP-1 and SREBP-2 cleavage by elevating ER phosphatidylethanolamine (PE), unlike PSS1 deficiency, which lowers PS and activates SREBP2. The 3.3 Å cryo-EM structure of human PSS2 reveals a smaller catalytic cavity that restricts substrate use to PE rather than PC.

Key findings

  • In Ptdss2−/− CHO-K1 cells, SREBP-1 and SREBP-2 cleavage was suppressed, including significantly reduced nuclear SREBP-1 and suppressed SREBP-2 cleavage; downstream SREBP pathway genes were also suppressed.
  • Ptdss2−/− cells showed no notable change in total PS versus WT, whereas Ptdss1−/− cells had considerably lower PS, indicating PSS1 is the major PS contributor in WT CHO-K1 cells. PSS2 mRNA was ~30% of PSS1 mRNA in WT CHO-K1 cells.
  • ER PE levels were substantially elevated in Ptdss2−/− cells and decreased in Ptdss1−/− cells versus WT, supporting the model that accumulated ER PE inhibits SREBP cleavage.
  • The human PSS2 cryo-EM structure at 3.3 Å with C2 symmetry shows a homodimer with 10 transmembrane helices per monomer, a PE density in the catalytic cavity, Ca2+ coordinated by Glu225, Glu228, Glu240, and Asp249, and two PS molecules in the cytosolic pocket. Substrate specificity is explained by a smaller catalytic cavity: F196 and F332 face inward in PSS2, while corresponding PSS1 residues F168 and F305 face away; MD simulations showed PC head-to-catalytic-histidine distances of ~3.5–4 Å versus >6 Å for PE.

Methods

  • WT, Ptdss1−/−, and Ptdss2−/− CHO-K1 cells generated by CRISPR-Cas9 were analyzed by RT-PCR, LC-MS/MS lipidomics, ER isolation via density gradient centrifugation, western blotting for SREBP processing, and quantitative real-time PCR.
  • Recombinant human PSS2 was expressed in HEK-293S GnTI− cells using baculovirus, purified via Flag affinity and size-exclusion chromatography, assayed for serine-exchange activity with POPE and L-serine, and imaged by cryo-EM at 3.3 Å; models were built using AlphaFold2 coordinates, COOT, PHENIX, and MolProbity.
  • Molecular dynamics simulations used CHARMM36 parameters and NAMD, with 100 ns production runs, to measure distances between PE/PC head groups and catalytic residues.

Limitations

  • The paper does not include an explicit limitations section.
  • Evident from the text: cryo-EM resolution limited model building, leaving residues 1–57 and 437–487 of PSS2 unbuilt; serine was tentatively modeled into the catalytic cavity; substrate-specificity conclusions rely partly on MD simulations over a 100 ns timescale.
  • The text states that the mechanism by which PSS1 activity, but not PSS2, regulates Asters-mediated cholesterol transport remains to be explored in future studies.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1073/pnas.2501177122

Cites

40 of 40 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

12 of 18 cited sources checked · 0 supported · 1 flagged · accuracy not yet measured

  • Interpretationreasoning

    The suppression of SREBP-1 and SREBP-2 cleavage by PSS2 deficiency is caused by elevated PE levels in the endoplasmic reticulum.

    “we show that PSS2 deficiency instead suppresses both SREBP-1 and SREBP-2 cleavage by elevating phosphatidylethanolamine (PE) levels in the endoplasmic reticulum.”
    • Also stated in: § Discussion · hedged
      “in the absence of PSS2, the accumulated PE in the ER would inhibit SREBP1 and SREBP2 cleavage.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] S. Rong, DGAT2 inhibition blocks SREBP-1 cleavage and improves hepatic steatosis by increasing phosphatidylethanolamine in the ER. Cell Metab. 36, 617– 629.e7 (2024). 38340721 PMC10939742 source

      In Results, under “PE enrichment suppresses SREBP-1 cleavage” (page unavailable), the paper says PE enrichment reduced nuclear SREBP-1 but did not significantly change nuclear SREBP-2. It studies DGAT2 inhibition, not PSS2 deficiency. Thus its finding is contrary to the attributed claim that elevated ER PE suppresses cleavage of both isoforms through PSS2 deficiency. (LLM, conf=0.90)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Findingown data

    Ptdss1 knockout reduces total PS levels in CHO-K1 cells.

    “The lipidomic analysis showed that the total amount of PS was considerably lower in Ptdss1−/− cells, consistent with a previous finding (15).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [15] D. Arikketh, R. Nelson, J. E. Vance, Defining the importance of phosphatidylserine synthase-1 (PSS1): Unexpected viability of PSS1-deficient mice. J. Biol. Chem. 283, 12888– 12897 (2008). 18343815 source

      The discussion of CHO mutants (section labeled Abstract in our copy; page unavailable) reports that PSS1-deficient CHO cells had 35–66% less PS. It does not identify those cells as CHO-K1 or establish that their PSS1 deficiency was a Ptdss1 knockout, so those specifics are not supported. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
  • Premiseown data

    The two mammalian phosphatidylserine synthases PSS1 and PSS2 have opposing roles in lipid regulation.

    “the two mammalian phosphatidylserine synthases, Phosphatidylserine synthases 1 and 2 (PSS1 and PSS2), have opposing roles in lipid regulation.”
    Quote in the paperSubstantial claim3 of 3 sources checked
    • cites [10] T. Long, Molecular insights into human phosphatidylserine synthase 1 reveal its inhibition promotes LDL uptake. Cell 187, 5665– 5678.e18 (2024). 39208797 PMC11455612 source

      The Introduction identifies PSS1 and PSS2 as the two mammalian phosphatidylserine synthases and describes different substrate preferences. The Results link PSS1 to cholesterol regulation, but our copy does not establish that PSS2 has an opposing role in lipid regulation. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
    • cites [11] M. N. Trinh, Interplay between Asters/GRAMD1s and phosphatidylserine in intermembrane transport of LDL cholesterol. Proc. Natl. Acad. Sci. U.S.A. 119, e2120411119 (2022). 34992143 PMC8764668 source

      The Abstract identifies PTDSS1 (PSS1) as a major phosphatidylserine-synthesizing enzyme in mammalian cells, and the Results link its loss to reduced cholesterol esterification. The passages do not describe PSS2 or compare the synthases, so they do not support the claimed opposing roles. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [12] J. Sandhu, Aster proteins facilitate nonvesicular plasma membrane to ER cholesterol transport in mammalian cells. Cell 175, 514– 529.e20 (2018). 30220461 PMC6469685 source

      The Discussion (page unavailable) says the Aster GRAM domain binds phosphatidylserine, but it does not discuss phosphatidylserine synthases. Searches for PSS1, PSS2, and phosphatidylserine synthase found no passage comparing their roles in lipid regulation. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • Findingown data

    Ptdss2 knockout increases PE levels in the endoplasmic reticulum.

    “elevating phosphatidylethanolamine (PE) levels in the endoplasmic reticulum”
    • Also stated in: § Results · plain
      “PE levels were substantially elevated in Ptdss2−/− cells and decreased in Ptdss1−/− cells (Fig. 2C), supporting our hypothesis.”
    • Also stated in: § Abstract · plain
      “Here, we found Ptdss2 knockout in CHO-K1 cells increased PE levels in the ER and is inclined to inhibit the cleavage of SREBPs.”
    Quote in the paperSubstantial claim
  • Findingown data

    PSS2 mRNA level is approximately 30% that of PSS1 in wild-type CHO-K1 cells.

    “the messenger RNA (mRNA) level of PSS2 is ~30% that of PSS1 in wild-type (WT) CHO-K1 cells (Fig. 1A).”
    Quote in the paperNot a substantial claim
  • It may state two separate claims as one. 12
  • Probably not a substantial claim. 4

  • It may state two separate claims as one.

    Findingown data

    SREBP1 and SREBP2 gene expression is increased in Ptdss1−/− cells.

    “we observed an increase in Srebp1 and Srebp2 gene expression from the Ptdss1−/− cells (10)”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [10] T. Long, Molecular insights into human phosphatidylserine synthase 1 reveal its inhibition promotes LDL uptake. Cell 187, 5665– 5678.e18 (2024). 39208797 PMC11455612 source

      The Results section (‘PSS1 inhibitor activates SREBP pathway and stimulates LDL uptake’; page unavailable) reports SREBP-2 cleavage in Ptdss1−/− cells, not increased Srebp1 or Srebp2 gene expression. The quantitative real-time PCR methods list primers for LDLR, but not either Srebp gene. Searches for Srebp1 and Srebp2 expression found no passage establishing the claimed increase. (LLM, conf=0.77)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim.

    Premisecitation

    An increase in PE levels in the endoplasmic reticulum can inhibit SREBP cleavage.

    “an increase in PE levels in the ER can inhibit SREBP cleavage (16).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] S. Rong, DGAT2 inhibition blocks SREBP-1 cleavage and improves hepatic steatosis by increasing phosphatidylethanolamine in the ER. Cell Metab. 36, 617– 629.e7 (2024). 38340721 PMC10939742 source

      The Results section, “PE enrichment suppresses SREBP-1 cleavage,” reports that increased ER PE blocks SREBP-1 processing. It also says the effect was specific to SREBP-1, not SREBP-2, so the claim’s unqualified reference to SREBP cleavage is broader than the finding. (LLM, conf=0.90)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    PSS1 and PSS2 use PE as a substrate to produce PS in the endoplasmic reticulum.

    “PSS1 and PSS2 (gene names: Ptdss1 and Ptdss2, respectively) use phosphatidylethanolamine (PE) as a substrate to produce PS in the endoplasmic reticulum (ER) (2, 3).”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [2] J. E. Vance, Historical perspective: Phosphatidylserine and phosphatidylethanolamine from the 1800s to the present. J. Lipid Res. 59, 923– 944 (2018). 29661786 PMC5983396 source

      Our copy says PS synthase-2 uses PE to make PS and places the active sites of both synthases on the cytosolic face of the ER. It does not support the claim that PSS1 also uses PE; the passage describing PSS1 instead distinguishes PC exchange from PSS2’s PE-to-PS activity. The supplied passages are labeled Abstract and have no page numbers. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [3] S. Tomohiro, A. Kawaguti, Y. Kawabe, S. Kitada, O. Kuge, Purification and characterization of human phosphatidylserine synthases 1 and 2. Biochem. J. 418, 421– 429 (2009). 19014349 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Ptdss2 knockout does not impair LDL-derived cholesterol trafficking from the plasma membrane to the endoplasmic reticulum.

    “unlike that in Ptdss1−/− cells, Ptdss2 knockout does not impair LDL-derived cholesterol trafficking from the PM to the ER (11).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [11] M. N. Trinh, Interplay between Asters/GRAMD1s and phosphatidylserine in intermembrane transport of LDL cholesterol. Proc. Natl. Acad. Sci. U.S.A. 119, e2120411119 (2022). 34992143 PMC8764668 source

      The Results report impaired LDL-cholesterol delivery to the ER in Ptdss1−/− cells, supporting the comparison in the citing sentence. The passages from our copy and a search for PTDSS2 do not address Ptdss2 knockout, so they do not support the claim that its loss leaves trafficking unimpaired. (LLM, conf=0.82)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Premisecitation

    PSS1 inhibition or deficiency reduces PS levels, thereby blocking Aster-mediated cholesterol transport to activate the SREBP2 pathway.

    “While PSS1 inhibition or deficiency reduces phosphatidylserine (PS) levels, thereby blocking Aster-mediated cholesterol transport to activate the SREBP2 pathway”
    • Also stated in: § Abstract · plain
      “inhibition of PSS1 can activate the SREBP2 pathway and influence cholesterol metabolism (10). This function is primarily achieved by a reduction in PSS1-mediated PS synthesis, which in turn prevents the transport of cholesterol by Asters proteins from the plasma membrane to the ER (11, 12).”
    Quote in the paperSubstantial claim3 of 3 sources checked
    • cites [10] T. Long, Molecular insights into human phosphatidylserine synthase 1 reveal its inhibition promotes LDL uptake. Cell 187, 5665– 5678.e18 (2024). 39208797 PMC11455612 source

      The Results section (‘PSS1 inhibitor activates SREBP pathway and stimulates LDL uptake’; page unavailable) says PS is indispensable for Aster-mediated cholesterol transport, reports that PSS1 depletion lowers intracellular PS and activates SREBP-2, and shows that a PSS1 inhibitor activates SREBP-2. It does not establish that inhibitor treatment lowers cellular PS or that Aster-mediated transport is blocked as the demonstrated causal step linking PSS1 inhibition to SREBP-2 activation. (LLM, conf=0.83)

      Experimental — accuracy not yet measured
    • cites [11] M. N. Trinh, Interplay between Asters/GRAMD1s and phosphatidylserine in intermembrane transport of LDL cholesterol. Proc. Natl. Acad. Sci. U.S.A. 119, e2120411119 (2022). 34992143 PMC8764668 source

      The Abstract reports that PTDSS1 deficiency reduces PS by 90% and impairs cholesterol transport to the ER; the Results report that LDL then suppresses SREBP-2 processing much less effectively. But the Discussion says Asters still contribute to transport in PS-deficient cells, so their transport is not completely blocked. The supplied passages address PTDSS1 deficiency, not inhibition. (LLM, conf=0.88)

      Experimental — accuracy not yet measured
    • cites [12] J. Sandhu, Aster proteins facilitate nonvesicular plasma membrane to ER cholesterol transport in mammalian cells. Cell 175, 514– 529.e20 (2018). 30220461 PMC6469685 source

      The Discussion says Asters bind phosphatidylserine, and the Results (‘Aster-B Promotes PM to ER Cholesterol Transport’; page unavailable) show that reducing Aster function increases SREBP-2 processing. Our copy does not report PSS1 inhibition or deficiency, reduced PS levels from PSS1 loss, or that such a reduction blocks Aster-mediated transport and activates SREBP-2. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Findingown data

    Downstream genes in the SREBP pathway are suppressed in Ptdss2−/− cells, but other genes such as Scap are not.

    “the expression of downstream genes in the SREBP pathway, but not the other genes (e.g., Scap), was also suppressed (Fig. 1F).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    PSS2 deficiency suppresses both SREBP-1 and SREBP-2 cleavage.

    “we show that PSS2 deficiency instead suppresses both SREBP-1 and SREBP-2 cleavage by elevating phosphatidylethanolamine (PE) levels in the endoplasmic reticulum.”
    • Also stated in: § Results · plain
      “SREBP-2 cleavage was suppressed in the Ptdss2−/− cells as well (Fig. 1E).”
    • Also stated in: § Results · plain
      “the nuclear form (N) of SREBP-1 is significantly suppressed (Fig. 1E).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    SREBP1 and SREBP2 gene expression is suppressed in Ptdss2−/− cells.

    “the expression of SREBP genes in Ptdss2−/− cells was suppressed (Fig. 1C).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    F196 and F332 face into the PSS2 catalytic cavity, while corresponding residues F168 and F305 in PSS1 face away from each other, enlarging the cavity to accommodate PC.

    “F196 and F332 face into the cavity but the corresponding residues (F168 and F305) in PSS1 face away from each other enlarging the cavity to accommodate PC (Fig. 3H).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    PSS2 forms a homodimer, with each monomer containing 10 transmembrane helices.

    “two PSS2 molecules form a homodimer, with each monomer containing 10 transmembrane helices (TMs).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Human PSS2 structure was determined by cryo-EM at 3.3 Å resolution with C2 symmetry.

    “We determined the structure of human PSS2 by cryo-EM at 3.3 Å resolution with C2 symmetry.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    MD simulations show that the distance between the catalytic histidine and the PC head methyl group remains approximately 3.5 to 4 Å, whereas the corresponding distance for the PE head group exceeds 6 Å.

    “the distance between the Nε2/Nδ1 of the catalytic histidine and the methyl group of the PC head remains ~3.5 to 4 Å, whereas the corresponding distance for the PE head group exceeds 6 Å (Fig. 3I).”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    Recombinant PSS2 has catalytic activity, whereas the catalytically dead mutant PSS2H200A does not.

    “recombinant PSS2 but not its catalytically dead mutant PSS2H200A presented reasonable activity”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [3] S. Tomohiro, A. Kawaguti, Y. Kawabe, S. Kitada, O. Kuge, Purification and characterization of human phosphatidylserine synthases 1 and 2. Biochem. J. 418, 421– 429 (2009). 19014349 source

  • It may state two separate claims as one.

    Premisecitation

    PSS2 is an endoplasmic reticulum-associated enzyme that utilizes PE as a substrate.

    “As an ER-associated enzyme that utilizes PE as a substrate”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [2] J. E. Vance, Historical perspective: Phosphatidylserine and phosphatidylethanolamine from the 1800s to the present. J. Lipid Res. 59, 923– 944 (2018). 29661786 PMC5983396 source

      Checked before — its earlier verdict is held back until a new check runs.

    • cites [3] S. Tomohiro, A. Kawaguti, Y. Kawabe, S. Kitada, O. Kuge, Purification and characterization of human phosphatidylserine synthases 1 and 2. Biochem. J. 418, 421– 429 (2009). 19014349 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premiseown data

    Human PSS1 and PSS2 are well conserved with approximately 40% amino acid sequence identity.

    “human PSS1 and PSS2 are well conserved with an amino acid sequence identify of ~40% (SI Appendix, Fig. S1)”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    PSS1 can utilize PC as a substrate, whereas PSS2 cannot.

    “PSS1 can also utilize phosphatidylcholine (PC) as its substrate, whereas PSS2 cannot (3).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [3] S. Tomohiro, A. Kawaguti, Y. Kawabe, S. Kitada, O. Kuge, Purification and characterization of human phosphatidylserine synthases 1 and 2. Biochem. J. 418, 421– 429 (2009). 19014349 source
16 of 16

  • The authors state this as an assumption.

    PSS2 employs its catalytic histidine H200 to deprotonate the hydroxyl group of serine, allowing it to attack the ester bond of PE to generate PS.

    “we speculate that PSS2 may employ its catalytic histidine (H200) to deprotonate the hydroxyl-group of serine allowing it to attack the ester bond of PE to generate PS (Fig. 3F).”
1 of 1

Self-check

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

Each contradiction between two passages listed here was confirmed by an independent check.

  • PHENIX refinement cites a Dali server reference

    Minor

    The Methods cite reference 22 for PHENIX refinement, but reference 22 is titled "Dali server," not PHENIX.

  • POPE concentration differs between the activity assay descriptions

    Minor

    The Results describe the recombinant PSS2 assay as using 200 mM POPE, whereas the Methods describe the serine-exchange assay under the same incubation conditions as using 200 μM POPE-a 1,000-fold difference.

  • Five-part membrane ratio lists only four components

    Minor

    The membrane composition specifies five ratio terms but names only four lipid components, leaving one term without a stated component.

3 of 3

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. D. Li X. Li Cryo-EM structure of human PSS2. RCSB Protein Data Bank. https://www.rcsb.org/structure/9N0X. Deposited 24 January 2025. · DOI

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Metadata

Authors
Li, D., Chen, H., Vale, G., Elghobashi-Meinhardt, N., Hatton, A., Rong, S., McDonald, J. G., & Li, X.
Affiliations
  • The University of Texas Southwestern Medical Center (US)
  • Center for Human Nutrition, University of Texas Southwestern Medical Center
  • School of Chemistry, University College Dublin
Corresponding author
Li, Xiaochun
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2025-05-15
Volume
122
Issue
20
Pages
e2501177122-e2501177122
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.2501177122
PMC
PMC12107096
OpenAlex
W4410398755
Cited by
6
References
39
Citations by year
2026: 6
FWCI
1.92
Type
journal article
Language
en
Open access
Licence
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion, cc-by-nc-nd)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
Funders
  • HHS | NIH | National Institute of General Medical Sciences (R35GM149533)
  • Welch Foundation (I-1957)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Biochemistry › Lipid metabolism and biosynthesis
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cancer Research › Cancer, Lipids, and Metabolism
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Sphingolipid Metabolism and Signaling
Keywords
SREBP1, SREBP2, phosphatidylethanolamine, substrate preference, phospholipid metabolism, endoplasmic reticulum, homologous enzymes, protein structure, lipidomics
MeSH terms
Animals, Endoplasmic Reticulum, Humans, Phosphatidylethanolamines, CDPdiacylglycerol-Serine O-Phosphatidyltransferase, Phosphatidylserines, Substrate Specificity, Cryoelectron Microscopy, Mice, Sterol Regulatory Element Binding Protein 1, Sterol Regulatory Element Binding Protein 2, Molecular Dynamics Simulation

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