Hsc70-4: An unanticipated mediator of dsRNA internalization in <i>Drosophila</i>.

ABSTRACT: The small interfering RNA pathway is the primary antiviral defense mechanism in invertebrates and plants. This systemic mechanism relies on the recognition, transport, and internalization of double-stranded RNA (dsRNA). Our aim was to identify cell surface proteins that bind extracellular dsRNA and mediate its internalization in Drosophila cells. We used coimmunoprecipitation coupled with proteomics analysis and found that silencing heat shock cognate protein 70-4 (Hsc70-4), a constitutively expressed heat shock protein, impairs dsRNA internalization. Unexpectedly, despite lacking a predicted transmembrane domain, Hsc70-4 localizes to the cell membrane via lipid interactions. Antibody blocking experiments revealed an extracellular domain on Hsc70-4 that is essential for dsRNA intern

SUBMITTER: Fletcher SJ 

PROVIDER: S-EPMC12083535 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature