CST complex subunit STN1 (STN1)

STN1 (CST complex subunit STN1) is a conserved protein and major component of the trimeric CST complex (composed of CTC1, STN1, TEN1 in humans; Cdc13, Stn1, Ten1 in yeast), which is essential for telomere maintenance and genome stability. STN1 contains an N-terminal oligonucleotide/oligosaccharide-binding (OB) fold and two winged helix-turn-helix (wHTH) motifs, mediating protein-protein interactions and single-stranded DNA binding. It functions by facilitating C-strand synthesis during telomere replication, participating in DNA replication fork rescue under stress, and interacting with other CST subunits and DNA polymerase α. Mutations in the STN1 gene disrupt telomere homeostasis, leading to Coat Plus syndrome and potentially other telomere dysfunction syndromes. CST complex and STN1 have additional non-telomeric roles in rescuing stalled replication forks genome-wide during replication stress. Although increasingly recognized for its role in human disease, STN1 is not a direct therapeutic target but may become relevant for molecular diagnostics or future therapeutic strategies targeting telomere biology.

Other names

OBFC1CST complex subunit STN1Oligonucleotide/oligosaccharide-binding fold-containing protein 1Suppressor of cdc thirteen homologCRMCC2RPA-32alpha accessory factor 44replication protein A 32 kDa subunitSTN1FLJ22559bA541N10.2AAF-44AAF44

Not directly targeted by existing drugs. Any mechanism would be indirect, e.g., modulation of CST complex activity via DNA replication or telomeric processes.