Sperm Protein Associated With The Nucleus, X-Linked Family, Member D (SPANXD)

By searching for genes in a SPANX gene cluster on chromosome X, Zendman et al. (2003) identified SPANXD. The deduced 97-amino acid protein contains a bipartite nuclear localization signal and a C-terminal GAL4 (LGALS4)-like domain. Westbrook et al. (2006) identified a PEST motif within the SPANXD protein. Using RT-PCR followed by restriction enzyme analysis to differentiate SPANXD and SPANXE from other SPANX transcripts, they found that SPANXD/E were expressed in 8 of 9 testicular mRNA samples examined, whereas SPANXB1 was expressed in all 9 samples.

Within the 5-prime flanking region of the SPANXD gene, they identified putative CCAAT and TATA boxes, an SRY site, and other potential DNA-binding domains. The upstream region also contains an Alu sequence