sperm-specific antigen 2; cleavage signal-1 protein; CS-1; Ki-ras-induced actin-interacting protein (SSFA2, CS1, KIAA1927, KRAP)

Function

• a 33 kD peptide corresponding to the C-terminus is found in the testis & seems to be cleaved into 2 peptides of 14 kD & 18 kD found on the surface of mature sperm cells
• this sperm surface antigen may be involved in some step of early cleavage of the fertilized oocyte

Compartment

• cytoplasm
• located near the plasma membrane
• associated with actin filaments
• may also exist as a membrane-bound form with extracellular regions

Alternative splicing

named isoforms=3

Expression

• strongly expressed in pancreas & testis
• present in colon cancer cells (at protein level)
• up-regulated by activated KRAS

More general terms

• phosphoprotein

Database

• UniProt: http://www.uniprot.org/uniprot/P28290.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6744
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6744
• OMIM: https://mirror.omim.org/entry/118990