Expression and identification of a novel gene Spata34 in mouse spermatogenic cells.

Leucine-rich repeat (LRR) containing proteins play an essential role in signal transduction, cell adhesion, cell development, DNA repair and RNA processing. Here we cloned a novel gene, Spata34, encoding a LRR containing protein of 415 aa. Spata34 gene consisted of 9 exons and 8 introns and mapped to chromosome 3qA3. Spata34 is conserved across species in evolution. The Spata34 gene was expressed at various levels, faintly before first weeks postpartum and strongly from 2 weeks postpartum in adult testes. Western blot analysis showed that Spata34 protein was specially expressed in mouse testis. Immunohistochemical analysis revealed that Spata34 protein was most abundant in the cytoplasm of round spermatids and elongating spermatids within seminiferous tubules of the adult testis. Overexpression of Spata34 in COS7 cells inhibited the transcriptional activity of AP-1, p53 and p21 which suggested that Spata34 protein may act as a transcriptional repressor in p53 and p21 pathway.