These notes summarize the literature on COL5A1, with experiment, species and precursor-product limits kept explicit. Automated literature synthesis was unavailable, so the assessment uses manually read sources.
COL5A1 supplies alpha1(V), commonly in the alpha1(V)2alpha2(V) heterotrimer and heterotypic collagen fibrils. Human EDS studies report abnormal fibril diameters, reduced type V secretion and disproportionately reduced matrix deposition/fibril number. The 15095409 abstract explicitly compares COL5A1-haploinsufficient cells with COL1A1-haploinsufficient OI cells; it is not a wrong-gene reference. Full originals 11278977/15095409 remain unavailable, so their exact biosynthesis assertions are UNDECIDED rather than treating secretion/deposition amounts as the performed chemical step. Intrinsic chain assembly can be work of formation; the review does not deny it simply because collagen is a precursor. PMID:11278977(https://pubmed.ncbi.nlm.nih.gov/11278977/), PMID:15095409(https://pubmed.ncbi.nlm.nih.gov/15095409/)
The complete 15383546 abstract reports mouse Col5a1 loss and failure of ordinary fibril formation, independently supporting initiation/structural work. This is not relabeled as a human assay. The integrated core uses existing GO:0030020, type V trimer and collagen fibril organization, rather than separate duplicate structural, receptor or processing cores. GO:0030020 explicitly permits extracellular-matrix collagens. PMID:15383546(https://pubmed.ncbi.nlm.nih.gov/15383546/)
PMID:20705069 treats V and XI as “a single collagen type with multiple tissue-specific isoforms” (Structure section), including alpha1(V)-containing type V trimers among the major V/XI isoforms. Its particular alpha1(XI)2alpha2(V) example is not a claim that alpha1(V) is absent from this family. The bovine cartilage/disc/meniscus study PMID:19103590 independently identifies alpha1(V) in crosslinked V/XI polymers and partially resolves alpha1(XI)/alpha1(V)/alpha3(XI) hybrids. Current GO:0005592 enumerates canonical alpha1(XI)/alpha2(XI)/alpha1(II), so the two existing source assertions are generalized to GO:0005583 (fibrillar collagen trimer). This is an existing-assertion correction, not a new coverage claim; the more specific hybrid composition is retained in the reasons and ontology question. PMID:20705069(https://pmc.ncbi.nlm.nih.gov/articles/PMC2996481/), PMID:19103590(https://pubmed.ncbi.nlm.nih.gov/19103590/)
The PMID:9042913 abstract independently links a C-propeptide cysteine substitution to failed mutant-chain trimer incorporation. This supports performed assembly work by the chain itself; the original biosynthesis assertions in PMID:11278977 and PMID:15095409 remain unresolved at their own assay scope because their full Methods were not recovered.
Both official products have 1838 residues and were independently reconstructed against genuine FASTAs. Isoform 2 replaces 1690–1711 in the C-propeptide; current annotations place signal 1–37, mature chain 38–1605 and C-propeptide 1606–1838. The mature-chain sequence is shared, but equal precursor selection, secretion and processing have not thereby been tested. The 9042913 abstract’s disease C-propeptide substitution is separate from these normal splice variants. PMID:9042913(https://pubmed.ncbi.nlm.nih.gov/9042913/)
The original 20979576 accepted manuscript was genuinely accessed as indexed author-uploaded text, with actual bait/library Methods, partner Table 1, selected co-IP controls, SPR and processing Results read. It uses the human alpha1(V) N-propeptide and engineered domains/constructs. Fibronectin, MMP2 and tenascin-C positive binary/domain evidence supports the respective partner-class refinements GO:0001968, GO:0002020 and GO:0050840, without an in-vivo colocalization, catalytic modulation or exact active-site requirement. TIMP1 and PCPE1 remain supported non-core binding; an inhibitor or processing enhancer is not automatically an enzyme. BMP1 processing assays are distinguished from the screen hits: no uninspected BMP1 binary retest is claimed. A model of matrix bridging is not made into a new adaptor function. The genuine selected abstract remains unchanged.
BioPlex reports four COL5A1 associations with MMP2 or PTPN2 in HEK293T cells. The canonical counterpart identities support protease binding (GO:0002020) and protein phosphatase binding (GO:0019903), respectively. These are AP-MS co-complex observations, including spoke-expanded MMP2 records; direct contact, native encounter and enzyme regulation remain unestablished. The N-propeptide/domain retests in PMID:20979576 supply a separate experimental context. The 2025 U2OS paper’s specific COL5A1/MMP2 entry remains unverified and is retained without a more specific claim. The interaction index preserves four matched records and eight source assertions without a current match; lack of a current match is not negative evidence against the original PMID:20979576 or PMID:9099729 observations. PMID:28514442(https://pubmed.ncbi.nlm.nih.gov/28514442/), PMID:33961781(https://pubmed.ncbi.nlm.nih.gov/33961781/), PMID:40205054(https://pubmed.ncbi.nlm.nih.gov/40205054/)
The original 9099729 Methods/Results use pepsinized human amniotic-membrane collagen V and rat NG2, with solid-phase and rotary-shadowing assays. Preserve the rat Q00657 partner, processed preparation and positive proteoglycan-core interaction. The 2203476 and 8900172 complete abstracts support heparin and PDGF binding respectively; full original Methods/preparation species remain uninspected, and aggregate affinities are not assigned to a particular human splice product. PMID:2203476(https://pubmed.ncbi.nlm.nih.gov/2203476/), PMID:8900172(https://pubmed.ncbi.nlm.nih.gov/8900172/)
Recovered 14970208 human Methods/Results distinguish COL5A1-deficient from COL3A1-deficient fibroblasts, purified human collagen V/III supplementation and integrin perturbations. They support matrix/fibronectin organization and a scoped integrin-ligand context, not purified alpha1(V)–integrin affinity. The broader fiber-organization assertion is retained because fibronectin and collagen networks are both involved.
The original 18305566 indexed paper uses human dermal fibroblasts and collagen V supplementation. Scratch-edge attachment stability and migration rescue are positive; this is not a separate quantitative adhesion assay. IGFBP1 Transwell is a different experiment. The epidermal-cell-specific wound-spreading assertion is refined to GO:0044319 (wound healing, spreading of cells); no epidermal cell was tested. The narrower fibroblast-migration term specifies pseudopodium extension/retraction, a mode not resolved by these saved assays, so it is not forced. Integrin organization/localization was assessed by immunofluorescence, whereas metabolic labeling concerned collagen; chemical integrin biosynthesis is not demonstrated. That exact process assertion is marked over-annotated while preserving every positive matrix, integrin, attachment and migration observation. The matrix-dependent movement restores a continuous monolayer surface, matching this wound-spreading parent without implying epidermal cells.
Actual 23154389 Methods/Results expose human ESCs to printed collagen V combinations under Wnt3a/ActivinA induction. The factorial effect reduces SOX17/DNA endoderm output; separate HEK293 adhesion controls are not ESC differentiation assays. Retain this applied matrix-cue effect as non-core, without claiming a universal endogenous receptor pathway or all-product equivalence. PMID:23154389(https://pubmed.ncbi.nlm.nih.gov/23154389/)
The 16431952 original indexed human examinations and separate mouse time-course Methods/Results support corneal/lid architecture and fibril changes. Human COL5A1 and COL5A2 cases stay separate. The 9683580 complete abstract supplies human splice/skin-disease evidence; proposed mutant incorporation is qualified. The 16430677 abstract is an Achilles-tendon association, not a demonstrated allele-specific assembly mechanism. These contextual observations are kept distinct from the performed matrix core. PMID:16431952(https://pubmed.ncbi.nlm.nih.gov/16431952/), PMID:9683580(https://pubmed.ncbi.nlm.nih.gov/9683580/), PMID:16430677(https://pubmed.ncbi.nlm.nih.gov/16430677/)
Nine exact original target-table rows were inspected: PMID:20551380 Table II row 89, PMID:25037231 complete-MS/Matrisome row 106, PMID:28344315 S2 row 18 and S3 A47/B31/C31/D26/E25. Several rows are different views of one source, not independent biological replications. PMID:20551380 and PMID:25037231 extraction Methods distinguish enriched extracellular protein detection from direct tensile measurements. The 28344315 complete article Methods remain unavailable despite authentic workbook access. The 27559042 and 28327460 selected normal caches remain partial. Their original full PMC HTML was recovered separately. PMID:27559042 human atrial extraction/MS Methods and Table 1 identify alpha1(V) in GuHCl input only, with blank glycoprotein/glycopeptide columns. PMID:28327460 cell-culture/quantification Methods and Table 1 list grouped COL5A1/2 as fibril-forming collagen V. These two additional original table entries are independently read; the grouped listing is not an alpha1(V)-specific peptide quantification. Expanded supplements remain uninspected, and no source cache was replaced. The 28675934 attempted XLSX is challenge HTML, and its target row remains unverified. Actual 27068509 vein extraction/MS Methods, Results and Figure3 legend explicitly identify CO5A1 in GuHCl extracts from six normal and six varicose saphenous veins. The tenfold plotting scale is not a biological fold change; no pixel value or uninspected supplemental target row is claimed. This establishes a target-specific textual link even without the workbook. Independently established extracellular/structural biology supports retention with these source limits explicit.
There are 60 IBA donor joins and 326 literal current same-term record occurrences. Official identity/taxon records and complete bounded GOA pages are pinned. Evidence classes remain literal, and current corroboration is not a reconstruction of historical PAINT tree/MSA/IBD placement. Target self-source is legitimate descendant grounding. Four IEA mouse joins are separate; the seed transfers are IEA even when donor records use other evidence codes. The basement-membrane donor has a current IDA 14676276 record, but the original available abstract foregrounds usherin/type IV, and genuine full recovery failed. The specific type V localization remains UNDECIDED without a wrong-gene accusation. The Reactome MrkD summary independently mentions type V on basement-membrane-associated tissues, but its underlying paper was not independently recovered; it does not retroactively verify the particular donor assay.
All 17 distinct Reactome summaries were read and target paths traced through 1260 actual graph paths. The source assertions remain separate. Type V degradation, N-propeptide partial removal, C-propeptide chain-dependent processing, secretion, fibril/fiber assembly and integrin/FN1/DDR1/VTN/DDR2/NCAM1/PDGF/MrkD/syndecan associations are distinct events. Matrix chains are not the enzymes that cleave them. ER-location sources describe precursor assembly/secretion; extracellular sources describe exported material. R-NUL-2731094 currently reports human and its identifier is preserved. Broad entity-set membership is not a direct assay of every isolated alpha chain or partner.
PMID:20979576 supports a new collagen-binding annotation (GO:0005518) for the tested human alpha1(V) N-propeptide and collagen preparations, without a new bridging process or an all-product affinity claim. Its current typed branch is protein-containing complex binding, with no ancestor/descendant overlap with the source or replacement MF terms. The confirmed TGF-beta1 interaction is retained in the biological evidence, but a separate GO:0050431 annotation would duplicate the existing GO:0005515 ancestor. The available PMID:37158802 review is full text; its precise COL5A1-specific link remains unverified despite accessible peptide-assembly/remodeling passages.
The PMID:20979576 accepted manuscript Table 1 (p.19, indexed lines 1739–1914) identifies FN1 1100–1292, TNC 1483–1622 and MMP2 346–660. Its co-IP Results state “No interaction was detected with four negative controls” (p.8, indexed lines 839–841), distinct from the assay-positive domains. Methods pp.6–7 describe the control design; the saved source-evidence locators identify the exact external windows. The three partner-class refinements also agree with the genuine abstract’s named interactions. The PMID:18305566 original Results report scratch-gap closure after collagen V supplementation (pp.1916–1917); Methods p.1919 distinguish this monolayer assay from the IGFBP1 Transwell experiment. The evidence index links each Reactome event and preserves its participant path; pathway membership is not an isolated alpha-chain affinity experiment.