U1 small nuclear ribonucleoprotein C (SNRPC)

Component of the spliceosomal U1 snRNP, which is essential for comprehension of the pre-mRNA 5' splice-site and the subsequent assembly of the spliceosome. SNRPC/U1-C is directly involved in initial 5' splice-site recognition for both constitutive and regulated alternative splicing.

The interaction with the 5' splice-site appears to precede base-pairing involving the pre-mRNA as well as the U1 snRNA. Stimulates devotion or early (E) complex formation by stabilizing the base pairing of the 5' end of the U1 snRNA and the 5' splice-site area.