Located near the plasma membrane. Associated with actin filaments. May also exist as a membrane-bound form with extracellular regions. Strongly expressed in pancreas and testis. Present in colon cancer cells (at protein level). Up-regulated by activated KRAS. A 33 kDa peptide corresponding to the C-terminus of this protein is found in the testis and seems to be cleaved into 2 peptides of 14 kDa and 18 kDa 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. Truncated N-terminus. Truncated N-terminus. Extended N-terminus. Truncated N-terminus.