The development of spermatogonial stem cells into spermatozoa, i.e., spermatogenesis, is a highly ordered process that requires multiple proteins, including some that are testis-specific or testis-specific isoforms of genes that are expressed in other tissues. One such protein is SPATA6: while its full-length isoform is expressed in multiple tissues including thymus, brain and testis, the shorter isoform is expressed only in testis. It has some homology to the motor domain of kinesin related proteins and with the C. elegans neural calcium sensor protein NCS-2.Synonyms: Spermatogenesis-associated protein 6