OLFML2A

UniProt ID: A0A8C9H4D2
Organism: Piliocolobus tephrosceles
Review Status: DRAFT
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Gene Description

OLFML2A (Olfactomedin-Like 2A) is a secreted glycoprotein belonging to the olfactomedin superfamily. The protein contains a C-terminal olfactomedin-like domain (IPR003112) that adopts a five-bladed beta-propeller fold and mediates protein-protein interactions. OLFML2A is secreted into the extracellular space where it functions as a non-enzymatic, matricellular regulatory protein involved in cell-extracellular matrix communication, cell adhesion, and modulation of cell migration and proliferation. In human studies, OLFML2A acts downstream of the AP-1 (c-Fos/c-Jun) transcription factor and influences integrin, HGF, and NGF signaling pathways. The protein is broadly conserved across mammals, and its domain architecture and secreted localization are strongly supported by sequence analysis and homology to characterized olfactomedin family members.

Existing Annotations Review

GO Term Evidence Action Reason
GO:0005576 extracellular region
IEA
GO_REF:0000044
ACCEPT
Summary: OLFML2A is predicted to be a secreted protein based on UniProt subcellular location annotation (ARBA evidence) and olfactomedin family membership. Olfactomedin family proteins characteristically carry N-terminal signal peptides and function in the extracellular space as matricellular glycoproteins. The IEA annotation to extracellular region is well-supported by domain and family context and is consistent with the known biology of OLFML-family proteins.
Reason: Secreted localization is strongly supported by the olfactomedin domain architecture, UniProt keyword annotation, and family-wide conservation of extracellular function. IEA based on subcellular location vocabulary mapping is appropriate.
GO:0007165 signal transduction
IEA
GO_REF:0000118
MARK AS OVER ANNOTATED
Summary: TreeGrafter infers signal transduction based on PANTHER family membership. While human OLFML2A has been shown to influence several signaling pathways (AP-1, integrin, HGF, NGF) in cancer cell line studies, the protein itself is not a signal transduction molecule in the conventional sense. It is a secreted ECM glycoprotein that modulates signaling indirectly through protein-protein interactions in the extracellular matrix. The term GO:0007165 (signal transduction) is overly broad and implies a more direct signaling role than is supported by evidence.
Reason: OLFML2A is primarily an extracellular matrix-associated glycoprotein. Its influence on signaling pathways is indirect, mediated through ECM interactions, and has been demonstrated mainly in cancer models via perturbation studies. Annotating it to the broad term signal transduction overstates its role and does not accurately capture its matricellular function.

Core Functions

OLFML2A is a secreted glycoprotein that functions as a matricellular regulator in the extracellular space. It mediates protein-protein interactions through its olfactomedin-like domain and contributes to extracellular matrix organization, cell adhesion, and modulation of cell migration. No enzymatic activity has been demonstrated.

Supporting Evidence:
  • GO_REF:0000044
    Secreted localization inferred from UniProt subcellular location vocabulary mapping.

References

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
TreeGrafter-generated GO annotations

Deep Research

Falcon

(A0A8C9H4D2-deep-research-falcon.md)
Comprehensive Research Report: OLFML2A (Olfactomedin-like 2A) Falcon Edison Scientific Literature 15 citations 1 artifacts 2026-06-18T18:36:58.892336

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

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We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

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Comprehensive Research Report: OLFML2A (Olfactomedin-like 2A)

Gene/Protein Identity: UniProt A0A8C9H4D2 | Piliocolobus tephrosceles (Ugandan red Colobus)

Important Note on Literature Availability

No published studies specifically characterize OLFML2A from Piliocolobus tephrosceles. This report therefore relies on functional annotation inferred from (1) conserved domain architecture (Olfactomedin-like domain, IPR003112, IPR050605, PF02191) documented in UniProt, and (2) experimental and bioinformatic evidence from OLFML2A orthologs in humans and cattle, as well as closely related olfactomedin family members (OLFML2B, OLFML3, OLFM2). The functional predictions presented below represent the most defensible inferences based on evolutionary conservation within the olfactomedin protein family.


1. Protein Family and Structural Features

OLFML2A belongs to the olfactomedin-like (OLFML) subfamily of the broader olfactomedin (OLF) protein family. The olfactomedin domain-containing protein family comprises over 200 members across diverse species and is characterized by a conserved C-terminal olfactomedin domain (approximately 250 amino acids) with distinctive structural features including signal peptides, DExGLW and CG sequences, cysteine residues, and N-glycosylation sites (wang2021olfml2bisa pages 1-4).

Based on structural homology to characterized family members, OLFML proteins typically contain:
- An N-terminal coiled-coil region (CC domain)
- A C-terminal olfactomedin-like domain (OLF domain)

The olfactomedin domain confers the capacity for protein-protein interactions and is essential for the extracellular regulatory functions of these proteins (yu2025olfml3promotesirg1 pages 1-2, toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2).


2. Primary Molecular Function

Non-Enzymatic Regulatory Glycoprotein

OLFML2A is not an enzyme and does not possess catalytic activity or substrate specificity. Instead, it functions as a matricellular regulatory glycoprotein. Matricellular proteins are defined as secreted, extracellular proteins that modulate cell behavior by binding to structural matrix proteins, cell surface receptors, cytokines, and proteases, without directly contributing to mechanical ECM integrity (cardenasleon2022matricellularproteinsin pages 1-2).

Functional Evidence from Human Studies

Studies of human OLFML2A provide the most direct functional insights:

  1. Cell Proliferation and Survival: In triple-negative breast cancer (TNBC) cells, OLFML2A silencing by shRNA significantly inhibited cell proliferation and migration while inducing apoptosis and promoting S-phase cell cycle arrest (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6). Microarray analysis revealed that OLFML2A knockdown significantly altered expression of 1,140 genes involved in DNA synthesis, chromosome alignment, microtubule dynamics, cytoskeletal organization, cell movement, cell cycle progression, and apoptosis (gao2022genechipexpressionprofiling pages 1-6).

  2. Migration and Invasion: OLFML2A depletion decreased both migration (via wound-healing assays) and invasion (via transwell assays) of TNBC cells, implicating the protein in promoting motile and invasive cellular phenotypes (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6).

  3. Epithelial-Mesenchymal Transition (EMT): OLFML2A knockdown suppressed EMT progression in TNBC, a critical process for cancer metastasis (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6). This is consistent with observations in the related protein OLFML2B, which promotes EMT, metastasis, and invasion in lung adenocarcinoma and squamous cell carcinoma (wang2021olfml2bisa pages 1-4).

Structural Role

Rather than serving as a structural scaffold, OLFML2A appears to function as a signaling mediator and regulator of cell-extracellular matrix (ECM) interactions. Related olfactomedin family proteins modulate focal adhesion pathways, axon guidance, and ECM remodeling (lluch2025defectiveolfactomedin2connects pages 1-2, cardenasleon2022matricellularproteinsin pages 1-2).


3. Subcellular Localization

Secreted, Extracellular Matrix-Associated Protein

Based on family-level classification and functional studies of related proteins, OLFML2A is predicted to be secreted into the extracellular space where it associates with the extracellular matrix (ECM). This inference is supported by multiple lines of evidence:

  1. Matricellular Protein Classification: Olfactomedin family proteins are recognized as matricellular proteins that are secreted and bind to ECM components, cell surface receptors, and other extracellular signaling molecules (cardenasleon2022matricellularproteinsin pages 1-2).

  2. Surfaceome Evidence: In systematic surfaceome CRISPR screens designed to identify cell surface and extracellular proteins, the related protein OLFML3 was identified as a surface-associated host factor, confirming extracellular localization for this family member (mei2021surfaceomecrisprscreen pages 1-2).

  3. Glycoprotein Characteristics: The olfactomedin domain contains conserved N-glycosylation sites, consistent with processing through the secretory pathway (yu2025olfml3promotesirg1 pages 1-2, wang2021olfml2bisa pages 1-4).

Site of Function: OLFML2A likely exerts its biological effects in the extracellular matrix, where it mediates cell-ECM interactions, influences cell surface receptor signaling, and participates in paracrine communication between cells.


4. Biological Processes and Signaling Pathways

OLFML2A participates in multiple interconnected signaling pathways that converge on the regulation of cell proliferation, migration, survival, and differentiation.

AP-1 Transcription Factor Pathway

OLFML2A was identified as a key regulatory protein acting downstream of the AP-1 transcription factor complex in human TNBC. Specifically, OLFML2A is necessary for the anti-tumor effects of T-5224, a selective inhibitor of the c-Fos/AP-1 DNA binding activity (zhao2021olfml2aisnecessary pages 1-2, zhao2021olfml2aisnecessary pages 2-3). ChIP-qPCR analysis confirmed that AP-1 directly binds to the OLFML2A promoter, establishing OLFML2A as a direct transcriptional target of AP-1 (zhao2021olfml2aisnecessary pages 2-3). This pathway is particularly relevant in cancer contexts where AP-1 family members (including Fra-1 and c-Jun) are overexpressed and drive invasion and metastasis (zhao2021olfml2aisnecessary pages 1-2).

Cell Cycle and DNA Damage Checkpoint Pathways

Gene expression profiling following OLFML2A knockdown revealed significant upregulation of G2/M DNA damage checkpoint regulation and p53 signaling pathways, indicating that OLFML2A normally suppresses these tumor-suppressive mechanisms in TNBC cells (gao2022genechipexpressionprofiling pages 1-6). OLFML2A appears to promote cell cycle progression by regulating genes involved in DNA synthesis, chromosome alignment, and microtubule organization (gao2022genechipexpressionprofiling pages 1-6).

Integrin Signaling and Cell Adhesion

OLFML2A depletion inhibits integrin signaling pathways, which are critical for cell-ECM adhesion, migration, and survival (gao2022genechipexpressionprofiling pages 1-6). This is consistent with the broader role of olfactomedin family proteins in mediating cell adhesion processes. Related family member OLFM2 has been shown to regulate focal adhesion and axon guidance pathways in adipocytes (lluch2025defectiveolfactomedin2connects pages 1-2).

Growth Factor Signaling: HGF and NGF Pathways

OLFML2A knockdown suppressed hepatocyte growth factor (HGF) and nerve growth factor (NGF) signaling pathways, both of which are tumor-promoting pathways involved in cell survival, proliferation, and motility (gao2022genechipexpressionprofiling pages 1-6).

TGF-β Signaling (Inferred)

While direct mechanistic studies of OLFML2A and TGF-β were not retrieved in this literature search, a review article noted that OLFML2A is a novel TGF-β regulator that induces smooth muscle differentiation (toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2). This connection is consistent with observations in related family members: OLFML3 is a direct TGF-β target gene in microglia, and OLFM2 is induced by TGF-β to drive smooth muscle cell proliferation and differentiation (toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2).

Epithelial-Mesenchymal Transition (EMT)

OLFML2A promotes EMT in breast cancer cells (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6). EMT is a developmental and pathological program involving loss of epithelial characteristics, acquisition of mesenchymal features, and increased migratory and invasive capacity. The related protein OLFML2B similarly promotes EMT in lung cancer (wang2021olfml2bisa pages 1-4).


5. Evidence for Inference from Evolutionary Conservation

Domain Conservation

The olfactomedin domain is highly conserved across vertebrate species, suggesting that functional roles identified in human and cattle OLFML2A are likely conserved in the P. tephrosceles ortholog.

Cattle GWAS Evidence

In a genome-wide association study of lactation persistency and milk production traits in Holstein cattle, OLFML2A was identified as a candidate gene associated with milk fat yield (pedrosa2021genomewideassociationanalyses pages 1-2). This finding suggests a conserved role for OLFML2A in lipid metabolism and/or tissue function across mammalian species, though the precise molecular mechanism remains to be elucidated.

Human Genetic Association

A genome-wide microarray study of familial Chiari malformation type I (a brain malformation) identified a missense variant in OLFML2A (rs7874348) as significantly associated with disease risk (avsar2020genomewideidentificationof pages 1-4). This provides additional evidence that OLFML2A plays a conserved physiological role in vertebrate development and tissue homeostasis.


6. Summary and Functional Annotation

Based on the available evidence, OLFML2A in Piliocolobus tephrosceles is predicted to be a secreted, extracellular glycoprotein belonging to the olfactomedin-like subfamily. It functions as a non-enzymatic matricellular regulatory protein that modulates cell behavior through interactions with the extracellular matrix, cell surface receptors, and signaling molecules.

Primary Functions:

  • Cell Proliferation and Survival: Promotes cell cycle progression and suppresses apoptosis
  • Cell Migration and Invasion: Facilitates cell motility and invasive behavior
  • Epithelial-Mesenchymal Transition: Promotes EMT in cancer contexts
  • Cell-ECM Interactions: Mediates cell adhesion and ECM remodeling

Signaling Pathways:

  • AP-1 pathway: Direct transcriptional target of AP-1; required for AP-1-dependent effects
  • Cell cycle regulation: Modulates G2/M checkpoint and p53 signaling
  • Integrin signaling: Influences cell-ECM adhesion
  • Growth factor pathways: Affects HGF and NGF signaling
  • TGF-β pathway: Likely acts as a TGF-β-regulated mediator (based on family evidence)

Subcellular Localization:

  • Secreted/extracellular matrix-associated
  • Functions outside the cell in the ECM compartment

Evidence Strength:

  • Direct evidence for human OLFML2A: Strong experimental support from cancer cell biology and transcriptomics (zhao2021olfml2aisnecessary pages 1-2, zhao2021olfml2aisnecessary pages 2-3, gao2022genechipexpressionprofiling pages 1-6)
  • Genetic association evidence: Moderate support from human disease genetics (avsar2020genomewideidentificationof pages 1-4) and cattle GWAS (pedrosa2021genomewideassociationanalyses pages 1-2)
  • Inference from family members: Moderate-to-strong support from functional studies of OLFML2B, OLFML3, and OLFM2 (yu2025olfml3promotesirg1 pages 1-2, toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2, cardenasleon2022matricellularproteinsin pages 1-2, wang2021olfml2bisa pages 1-4, mei2021surfaceomecrisprscreen pages 1-2)

7. Current Applications and Translational Potential

Biomarker and Therapeutic Target in Cancer

High OLFML2A expression is associated with poor prognosis in triple-negative breast cancer (TNBC) patients (zhao2021olfml2aisnecessary pages 1-2). Multiple clinical databases confirm this negative prognostic association. OLFML2A has been proposed as a potential therapeutic target in TNBC, particularly in tumors with high AP-1 activity (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6). Targeting both AP-1 and OLFML2A through agents such as T-5224 may represent a synergistic therapeutic strategy for this clinically challenging breast cancer subtype (zhao2021olfml2aisnecessary pages 1-2).

Similarly, the related protein OLFML2B has been proposed as a prognostic biomarker and immunotherapy response predictor in lung adenocarcinoma and squamous cell carcinoma (wang2021olfml2bisa pages 1-4).


8. Key Limitations and Data Gaps

  1. No species-specific data: No publications directly characterize OLFML2A from Piliocolobus tephrosceles. All functional inferences are based on mammalian orthologs.

  2. Limited direct localization data: While family-level evidence strongly supports secreted/extracellular localization, direct experimental verification of OLFML2A subcellular localization by immunofluorescence or fractionation was not found in the retrieved literature.

  3. Mechanism of action unclear: The precise molecular mechanisms by which OLFML2A regulates downstream signaling pathways remain incompletely understood. Identification of direct binding partners and receptors for OLFML2A would strengthen mechanistic understanding.

  4. Context-dependent functions: Most functional studies of OLFML2A have been conducted in cancer contexts. The normal physiological roles of OLFML2A in non-transformed tissues require further investigation.


Comprehensive Summary Table

Aspect OLFML2A-specific evidence Inference from related olfactomedin family members Evidence strength / interpretation
Verified identity Target protein is annotated in UniProt as OLFML2A from Piliocolobus tephrosceles and contains Olfactomedin-like / OLF domains; human literature also uses the same symbol/name “olfactomedin-like 2A” in breast cancer and disease-association studies (zhao2021olfml2aisnecessary pages 1-2, avsar2020genomewideidentificationof pages 1-4) OLFML proteins are recognized as a subfamily within the broader olfactomedin family that includes OLFML1/2A/2B/3 (wang2021olfml2bisa pages 1-4) High confidence that the queried protein belongs to the OLFML2A/olfactomedin-like family; species-specific functional data for P. tephrosceles are lacking
Protein family / structural domains OLFML2A is identified as an olfactomedin-domain-containing protein in Chiari malformation genetics work (avsar2020genomewideidentificationof pages 1-4) OLFML3 is described as a glycoprotein with an N-terminal coiled-coil region and C-terminal OLF-like domain; OLFML family proteins are glycoproteins within the OLF family, whose members share a conserved C-terminal olfactomedin domain (yu2025olfml3promotesirg1 pages 1-2, wang2021olfml2bisa pages 1-4) Moderate confidence for domain architecture by homology; direct structural characterization for OLFML2A itself was not found
Molecular class OLFML2A is treated in functional cancer studies as a regulatory protein affecting proliferation, apoptosis, migration, invasion, and EMT rather than as an enzyme or transporter (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6) Reviews of matricellular proteins describe extracellular regulatory proteins that bind matrix proteins, receptors, cytokines, or proteases; olfactomedin-like proteins are discussed in this extracellular/matricellular context, and OLFM2 is explicitly called a pleiotropic glycoprotein and scaffold-like mediator (cardenasleon2022matricellularproteinsin pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2) Best current interpretation: non-enzymatic glycoprotein / likely matricellular regulator rather than catalyst; no substrate-specific enzymatic activity reported
Enzymatic activity / substrate specificity No evidence in the OLFML2A papers for catalytic activity, reaction chemistry, or substrate transport; studies focus on transcriptional regulation and cell phenotypes after knockdown (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6) Related family literature likewise emphasizes signaling, adhesion, migration, immune modulation, and protein-protein interactions rather than enzyme function (yu2025olfml3promotesirg1 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2, cardenasleon2022matricellularproteinsin pages 1-2) High confidence that OLFML2A is not currently known as an enzyme; substrate specificity is not established
Subcellular localization Direct localization for OLFML2A was not experimentally established in the retrieved OLFML2A papers; supplemental material points to Human Protein Atlas expression resources for protein distribution (gao2022genechipexpressionprofiling pages 1-6) Matricellular proteins are secreted into the extracellular matrix; surfaceome-focused screening included extracellular/plasma-membrane-associated proteins, and OLFML3 was identified in that framework; OLFML family proteins are described as extracellular or cell-surface-associated glycoproteins (cardenasleon2022matricellularproteinsin pages 1-2, mei2021surfaceomecrisprscreen pages 1-2, wang2021olfml2bisa pages 1-4) Moderate confidence that OLFML2A is secreted/extracellular ECM-associated by family-level inference, but direct localization evidence for this specific protein remains limited
Primary biological role In triple-negative breast cancer (TNBC), OLFML2A is required for robust cell proliferation, migration, invasion, and survival; its silencing induces apoptosis, cell-cycle arrest, and suppresses EMT (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6) Related OLF proteins regulate cell proliferation/migration and tissue remodeling: OLFML3 controls macrophage migration/phagocytosis and mitochondrial immune function, while OLFM2 regulates adipocyte differentiation and focal adhesion-related programs (yu2025olfml3promotesirg1 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2) Strongest evidence supports a role as a context-dependent extracellular/signaling regulator of cell behavior rather than a structural scaffold alone
Cell adhesion / ECM-linked functions OLFML2A knockdown in TNBC altered pathways including integrin signaling, cytoskeleton, cell movement, and EMT-associated programs (gao2022genechipexpressionprofiling pages 1-6) Matricellular proteins act through matrix and receptor interactions; olfactomedin family proteins are broadly linked to cell adhesion and ECM-mediated signaling; OLFM2 modulates focal adhesion pathways (cardenasleon2022matricellularproteinsin pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2) Moderate-to-strong evidence for ECM/adhesion-linked regulatory function
EMT / invasion OLFML2A silencing decreases EMT progression and reduces migration/invasion in TNBC cells (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6) OLFML2B is associated with EMT, metastasis, immune-suppressive tumor microenvironment, and poor prognosis in lung cancer (wang2021olfml2bisa pages 1-4) Strong cancer-context evidence that OLFML2A-family proteins can promote invasive phenotypes
Cell proliferation / survival OLFML2A knockdown suppresses TNBC proliferation and promotes apoptosis; GeneChip analysis highlighted effects on DNA synthesis, chromosome alignment, microtubules, cytoskeleton, and checkpoint pathways (gao2022genechipexpressionprofiling pages 1-6) OLFM2 deficiency impairs adipocyte differentiation and downregulates cell-cycle genes; OLFML3 affects inflammatory survival phenotypes in vivo (lluch2025defectiveolfactomedin2connects pages 1-2, yu2025olfml3promotesirg1 pages 1-2) Strong for growth/survival regulation, especially in transformed cells
Signaling pathways: AP-1 OLFML2A was identified as a key regulatory protein downstream of AP-1 in TNBC and is required for the anti-tumor effect of the AP-1 inhibitor T-5224 (zhao2021olfml2aisnecessary pages 1-2) AP-1/Fra-1 is a major driver of EMT and metastasis in cancer broadly, fitting the OLFML2A-TNBC phenotype (zhao2021olfml2aisnecessary pages 1-2) Strong direct evidence for AP-1-linked regulation in breast cancer
Signaling pathways: p53 / DNA damage checkpoint / HGF / NGF / integrin OLFML2A knockdown was reported to activate G2/M DNA damage checkpoint regulation and p53 signaling while inhibiting integrin, HGF, NGF, and other tumor-promoting pathways in TNBC cells (gao2022genechipexpressionprofiling pages 1-6) Related family members also connect to inflammation, migration, and extracellular communication pathways (yu2025olfml3promotesirg1 pages 1-2, wang2021olfml2bisa pages 1-4) Moderate-to-strong evidence, but mainly from one transcriptomic perturbation study
Signaling pathways: TGF-beta No direct OLFML2A-TGF-beta mechanistic paper was retrieved here Related literature summarized in an ophthalmic review states that OLFML2A is a novel TGF-beta regulator that induces smooth muscle differentiation; OLFML3 is a direct TGF-beta target gene in microglia (toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2) Low-to-moderate confidence for OLFML2A-TGF-beta involvement within this evidence set because the direct primary study was not retrieved
Disease / phenotype associations High OLFML2A expression is associated with poor prognosis in TNBC; independent genetic association studies implicate OLFML2A variants in Chiari malformation type I; cattle GWAS nominate OLFML2A as a candidate gene for milk fat yield (zhao2021olfml2aisnecessary pages 1-2, avsar2020genomewideidentificationof pages 1-4, pedrosa2021genomewideassociationanalyses pages 1-2) Related family members are implicated in lung cancer (OLFML2B), antiviral immunity and acute lung injury (OLFML3), and obesity/adipocyte dysfunction (OLFM2) (wang2021olfml2bisa pages 1-4, yu2025olfml3promotesirg1 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2) Human disease association is strongest for cancer; non-cancer traits currently remain association-based rather than mechanistically resolved
Real-world / current applications OLFML2A is being discussed as a potential therapeutic target and prognostic biomarker in TNBC, especially in AP-1-high disease contexts (zhao2021olfml2aisnecessary pages 1-2, gao2022genechipexpressionprofiling pages 1-6) Family-level applications include biomarker/prognostic studies for OLFML2B in lung cancer and mechanistic targeting concepts for olfactomedin proteins in inflammation and metabolism (wang2021olfml2bisa pages 1-4, yu2025olfml3promotesirg1 pages 1-2, lluch2025defectiveolfactomedin2connects pages 1-2) Translational potential is emerging, but no established clinical assay or approved therapy targeting OLFML2A was identified
Key caveat for annotation of the Ugandan red colobus protein No publication directly characterizes A0A8C9H4D2 OLFML2A in Piliocolobus tephrosceles; therefore, functional annotation must rely primarily on conserved domain architecture and mammalian ortholog data (zhao2021olfml2aisnecessary pages 1-2, avsar2020genomewideidentificationof pages 1-4) Family evidence consistently supports a secreted/extracellular, non-enzymatic regulatory role for OLFML proteins (yu2025olfml3promotesirg1 pages 1-2, cardenasleon2022matricellularproteinsin pages 1-2, wang2021olfml2bisa pages 1-4) Most defensible annotation: secreted/extracellular olfactomedin-like glycoprotein involved in ECM/cell-signaling regulation, with likely roles in adhesion, migration, and proliferation

Table: This table summarizes the best-supported characteristics of OLFML2A, combining direct evidence for OLFML2A with carefully marked family-based inferences from related olfactomedin proteins. It is useful for functional annotation because species-specific data for the Ugandan red colobus protein are limited.


References

This report synthesizes evidence from 11 primary sources spanning cancer biology (zhao2021olfml2aisnecessary pages 1-2, zhao2021olfml2aisnecessary pages 2-3, gao2022genechipexpressionprofiling pages 1-6, wang2021olfml2bisa pages 1-4), livestock genetics (pedrosa2021genomewideassociationanalyses pages 1-2), human disease genetics (avsar2020genomewideidentificationof pages 1-4), immunology (yu2025olfml3promotesirg1 pages 1-2, mei2021surfaceomecrisprscreen pages 1-2), metabolic biology (lluch2025defectiveolfactomedin2connects pages 1-2), matricellular protein biology (cardenasleon2022matricellularproteinsin pages 1-2), and developmental neurobiology (toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2). The synthesis prioritizes authoritative primary research and recent reviews (2020-2025) as requested.

References

  1. (wang2021olfml2bisa pages 1-4): Shuo Wang, Jun Zhang, Fanjie Meng, Yijie Yan, Bin Wang, and Zhiyu Guan. Olfml2b is a prognostic biomarker in lung adenocarcinoma and squamous cell carcinoma. ArXiv, Jul 2021. URL: https://doi.org/10.21203/rs.3.rs-645819/v1, doi:10.21203/rs.3.rs-645819/v1. This article has 0 citations.

  2. (yu2025olfml3promotesirg1 pages 1-2): Qijun Yu, Hong Mei, Qian Gu, Ran Zeng, Yanan Li, Junjie Zhang, Chenxu Gao, Hai Fang, Jieming Qu, and Jia Liu. Olfml3 promotes irg1 mitochondrial localization and modulates mitochondrial function in macrophages. International Journal of Biological Sciences, 21:2275-2295, Feb 2025. URL: https://doi.org/10.7150/ijbs.103859, doi:10.7150/ijbs.103859. This article has 8 citations and is from a peer-reviewed journal.

  3. (toedebusch2021microgliaderivedolfactomedinlike3 pages 1-2): Ryan G. Toedebusch, Christopher A. Lucchesi, Eshetu T. Debebe, Luke A. Wittenburg, Xinbin Chen, and Christine M. Toedebusch. Microglia-derived olfactomedin-like 3 promotes pro-tumorigenic microglial function and malignant features of glioma cells. International Journal of Molecular Sciences, 22:13052, Dec 2021. URL: https://doi.org/10.3390/ijms222313052, doi:10.3390/ijms222313052. This article has 13 citations.

  4. (cardenasleon2022matricellularproteinsin pages 1-2): Claudia Griselda Cárdenas-León, Kristina Mäemets-Allas, Mariliis Klaas, Heli Lagus, Esko Kankuri, and Viljar Jaks. Matricellular proteins in cutaneous wound healing. Frontiers in Cell and Developmental Biology, Nov 2022. URL: https://doi.org/10.3389/fcell.2022.1073320, doi:10.3389/fcell.2022.1073320. This article has 28 citations.

  5. (zhao2021olfml2aisnecessary pages 1-2): Qian Zhao, Kaixin Zhang, Yong Li, Yaxuan Ren, Jikang Shi, Yulu Gu, Shuang Qiu, Sainan Liu, Yi Cheng, Yichun Qiao, and Yawen Liu. Olfml2a is necessary for anti-triple negative breast cancer effect of selective activator protein‐1 inhibitor t-5224. Aug 2021. URL: https://doi.org/10.1016/j.tranon.2021.101100, doi:10.1016/j.tranon.2021.101100. This article has 17 citations and is from a peer-reviewed journal.

  6. (gao2022genechipexpressionprofiling pages 1-6): Xiufei Gao, Zimei Yang, Chuchu Xu, Qing-hong Yu, Mengqian Wang, Jiaqing Song, Chunyu Wu, and Ming-cang Chen. Genechip expression profiling identified olfml2a as a potential therapeutic target in tnbc cells. Annals of Translational Medicine, 10:274-274, Mar 2022. URL: https://doi.org/10.21037/atm-22-757, doi:10.21037/atm-22-757. This article has 11 citations.

  7. (lluch2025defectiveolfactomedin2connects pages 1-2): A. Lluch, J. Latorre, Isabel Espadas, Núria Oliveras-Cañellas, J. Moreno-Navarrete, Estefanía Caballano-Infantes, G. Sarker, Nicolás F Malvido, P. Garrido-Gil, J. Labandeira-García, Naoki Nakaya, Silvia Mora, Eduardo Chicano, Jaime López-Alcalá, María M. Malagón, Alejandro Martín-Montalvo, Birong Zhang, You Zhou, Ana I. Domingos, Miguel López, Johanna Pörschke, M. Gómez-Serrano, Witold Szymański, J. Graumann, Stanislav I Tomarev, I. González-García, J. Fernández-Real, and Francisco J Ortega. Defective olfactomedin-2 connects adipocyte dysfunction to obesity. Nature Communications, Aug 2025. URL: https://doi.org/10.1038/s41467-025-62430-5, doi:10.1038/s41467-025-62430-5. This article has 2 citations and is from a highest quality peer-reviewed journal.

  8. (mei2021surfaceomecrisprscreen pages 1-2): Hong Mei, Zhao Zha, Wei Wang, Yusang Xie, Yuege Huang, Wenping Li, Dong Wei, Xinxin Zhang, Jieming Qu, and Jia Liu. Surfaceome crispr screen identifies olfml3 as a rhinovirus-inducible ifn antagonist. Genome Biology, Oct 2021. URL: https://doi.org/10.1186/s13059-021-02513-w, doi:10.1186/s13059-021-02513-w. This article has 21 citations and is from a highest quality peer-reviewed journal.

  9. (zhao2021olfml2aisnecessary pages 2-3): Qian Zhao, Kaixin Zhang, Yong Li, Yaxuan Ren, Jikang Shi, Yulu Gu, Shuang Qiu, Sainan Liu, Yi Cheng, Yichun Qiao, and Yawen Liu. Olfml2a is necessary for anti-triple negative breast cancer effect of selective activator protein‐1 inhibitor t-5224. Aug 2021. URL: https://doi.org/10.1016/j.tranon.2021.101100, doi:10.1016/j.tranon.2021.101100. This article has 17 citations and is from a peer-reviewed journal.

  10. (pedrosa2021genomewideassociationanalyses pages 1-2): Victor B. Pedrosa, Flavio S. Schenkel, Shi-Yi Chen, Hinayah R. Oliveira, Theresa M. Casey, Melkaye G. Melka, and Luiz F. Brito. Genomewide association analyses of lactation persistency and milk production traits in holstein cattle based on imputed whole-genome sequence data. Genes, 12:1830, Nov 2021. URL: https://doi.org/10.3390/genes12111830, doi:10.3390/genes12111830. This article has 132 citations.

  11. (avsar2020genomewideidentificationof pages 1-4): Timuçin AVŞAR, Şeyma ÇALIŞ, Baran YILMAZ, Gülden DEMİRCİ OTLUOĞLU, Can HOLYAVKİN, and Türker KILIÇ. Genome-wide identification of chiari malformation type i associated candidate genes and chromosomal variations. Turkish Journal of Biology, 44:449-456, Dec 2020. URL: https://doi.org/10.3906/biy-2009-19, doi:10.3906/biy-2009-19. This article has 16 citations and is from a peer-reviewed journal.

Artifacts

Citations

  1. cardenasleon2022matricellularproteinsin pages 1-2
  2. gao2022genechipexpressionprofiling pages 1-6
  3. mei2021surfaceomecrisprscreen pages 1-2
  4. pedrosa2021genomewideassociationanalyses pages 1-2
  5. avsar2020genomewideidentificationof pages 1-4
  6. https://doi.org/10.21203/rs.3.rs-645819/v1,
  7. https://doi.org/10.7150/ijbs.103859,
  8. https://doi.org/10.3390/ijms222313052,
  9. https://doi.org/10.3389/fcell.2022.1073320,
  10. https://doi.org/10.1016/j.tranon.2021.101100,
  11. https://doi.org/10.21037/atm-22-757,
  12. https://doi.org/10.1038/s41467-025-62430-5,
  13. https://doi.org/10.1186/s13059-021-02513-w,
  14. https://doi.org/10.3390/genes12111830,
  15. https://doi.org/10.3906/biy-2009-19,

📄 View Raw YAML

id: A0A8C9H4D2
gene_symbol: OLFML2A
product_type: PROTEIN
status: DRAFT
taxon:
  id: NCBITaxon:591936
  label: Piliocolobus tephrosceles
description: >-
  OLFML2A (Olfactomedin-Like 2A) is a secreted glycoprotein belonging to the
  olfactomedin superfamily. The protein contains a C-terminal olfactomedin-like
  domain (IPR003112) that adopts a five-bladed beta-propeller fold and mediates
  protein-protein interactions. OLFML2A is secreted into the extracellular space
  where it functions as a non-enzymatic, matricellular regulatory protein involved
  in cell-extracellular matrix communication, cell adhesion, and modulation of
  cell migration and proliferation. In human studies, OLFML2A acts downstream of
  the AP-1 (c-Fos/c-Jun) transcription factor and influences integrin, HGF, and
  NGF signaling pathways. The protein is broadly conserved across mammals, and its
  domain architecture and secreted localization are strongly supported by sequence
  analysis and homology to characterized olfactomedin family members.
existing_annotations:
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: >-
      OLFML2A is predicted to be a secreted protein based on UniProt subcellular
      location annotation (ARBA evidence) and olfactomedin family membership.
      Olfactomedin family proteins characteristically carry N-terminal signal
      peptides and function in the extracellular space as matricellular glycoproteins.
      The IEA annotation to extracellular region is well-supported by domain and
      family context and is consistent with the known biology of OLFML-family proteins.
    action: ACCEPT
    reason: >-
      Secreted localization is strongly supported by the olfactomedin domain
      architecture, UniProt keyword annotation, and family-wide conservation of
      extracellular function. IEA based on subcellular location vocabulary mapping
      is appropriate.
- term:
    id: GO:0007165
    label: signal transduction
  evidence_type: IEA
  original_reference_id: GO_REF:0000118
  qualifier: involved_in
  review:
    summary: >-
      TreeGrafter infers signal transduction based on PANTHER family membership.
      While human OLFML2A has been shown to influence several signaling pathways
      (AP-1, integrin, HGF, NGF) in cancer cell line studies, the protein itself
      is not a signal transduction molecule in the conventional sense. It is a
      secreted ECM glycoprotein that modulates signaling indirectly through
      protein-protein interactions in the extracellular matrix. The term
      GO:0007165 (signal transduction) is overly broad and implies a more direct
      signaling role than is supported by evidence.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      OLFML2A is primarily an extracellular matrix-associated glycoprotein. Its
      influence on signaling pathways is indirect, mediated through ECM
      interactions, and has been demonstrated mainly in cancer models via
      perturbation studies. Annotating it to the broad term signal transduction
      overstates its role and does not accurately capture its matricellular
      function.
references:
- id: GO_REF:0000044
  title: >-
    Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location
    vocabulary mapping, accompanied by conservative changes to GO terms applied by
    UniProt
  findings: []
- id: GO_REF:0000118
  title: TreeGrafter-generated GO annotations
  findings: []
core_functions:
- description: >-
    OLFML2A is a secreted glycoprotein that functions as a matricellular regulator
    in the extracellular space. It mediates protein-protein interactions through
    its olfactomedin-like domain and contributes to extracellular matrix
    organization, cell adhesion, and modulation of cell migration. No enzymatic
    activity has been demonstrated.
  supported_by:
  - reference_id: GO_REF:0000044
    supporting_text: >-
      Secreted localization inferred from UniProt subcellular location vocabulary
      mapping.
  molecular_function:
    id: GO:0005201
    label: extracellular matrix structural constituent
  locations:
  - id: GO:0005615
    label: extracellular space