SRP14 Human
Description
Core SRP Function
SRP14 facilitates ER targeting by transiently arresting translation upon signal sequence recognition, ensuring proper protein localization .
Non-Canonical Roles
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Alu RNA Regulation: Binds Alu RNAs derived from retrotransposons, influencing their maturation, trafficking, and roles in stress responses .
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HIV-1 Latency Control: Modulates HIV-1 Tat expression, with overexpression reactivating latent virus in CD4+ T-cells (Fig. 6) .
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Translational Regulation: Associates with IRES elements to modulate Tat synthesis during viral replication .
Genetic and Biochemical Variants
The P124A mutation (Proline→Alanine at residue 124) alters SDS-PAGE migration patterns without significantly impacting function (Fig. 2) . This mutation highlights structural plasticity in SRP14's alanine-rich tail.
| Cell Line | SRP14 Migration Pattern | Mutation Status |
|---|---|---|
| HCT116, HEK293T | Faster migration | P124A present |
| HeLa, LoVo | Slower migration | Wild-type |
Viral Infections
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HIV-1: SRP14 expression correlates with viral reactivation in latently infected T-cells (MFI increase: 1.3–2.5 fold) .
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HCV: Interacts with viral RNA to influence replication cycles .
Cancer
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Hepatocellular Carcinoma: Elevated SRP14 expression associates with advanced tumor stages and reduced survival .
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ER Stress Response: PERK-mediated SRP14 degradation alleviates ER stress in cancer cells .
Key Findings
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SRP9/SRP14 knockdown reduces 7SL RNA levels by >50% across cell lines (A549, HEK293T) .
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HMGB3 and SRP14 inversely regulate Tat expression, suggesting therapeutic targets for HIV latency .
Limitations
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Most studies use transformed cell lines (e.g., J-Lat), limiting extrapolation to primary T-cells .
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Mechanistic details of SRP14’s nuclear roles in Alu RNA processing remain unresolved .
Future Directions
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Investigate SRP14's role in retrotransposon-mediated genomic instability.
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Develop SRP14-targeted therapies for HIV latency reversal.
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Explore tissue-specific SRP14 isoforms in cancer progression.
Product Specs
Product Science Overview
Signal Recognition Particle 14kDa (SRP14) is a crucial component of the signal recognition particle (SRP) complex, which plays a vital role in the targeting and translocation of proteins to the endoplasmic reticulum (ER). This process is essential for the proper functioning of cellular activities, as it ensures that proteins are correctly localized within the cell.
SRP14 is a ribonucleoprotein complex that forms a heterodimer with SRP9. This heterodimer binds to the 5’ and 3’ terminal sequences of SRP RNA, forming the “Alu domain” of the SRP . The binding of SRP9/14 to SRP RNA is crucial for the transcription, maturation, nucleolus localization, and transport of SRP RNA .
The SRP complex, including SRP14, mediates the targeting of nascent polypeptide chains to the ER membrane. This targeting is achieved through the recognition of signal sequences on the nascent polypeptides by the SRP, which then directs the ribosome-nascent chain complex to the ER membrane .
Recombinant human SRP14 is a version of the protein that has been produced using recombinant DNA technology. This involves inserting the gene encoding SRP14 into a suitable expression system, such as E. coli, to produce the protein in large quantities . The recombinant SRP14 protein is often tagged with a His-tag at the N-terminus to facilitate purification and detection .
The recombinant human SRP14 protein is typically used in research to study the function and structure of the SRP complex, as well as its role in protein targeting and translocation. It is also used in various biochemical assays and structural studies to understand the interactions between SRP14 and other components of the SRP complex .
Recent studies have highlighted the potential clinical significance of SRP14. For instance, high expression levels of SRP14 have been associated with poor prognosis in patients with acute myeloid leukemia (AML) . Genome-wide co-expression analysis suggests that SRP14 may play a role in AML by participating in the regulation of various biological processes and signaling pathways, such as cell cycle, cell adhesion, and NF-κB signaling .
