A novel gonadotropin-regulated testicular RNA helicase - A new member of the DEAD-box family

A gonadotropin-regulated testicular RNA helicase (GRTH) was identified and characterized GRTH cloned from rat Leydig cell, mouse testis, and human tes tis cDNA Libraries is a novel member of the DEAD-box protein family. GRTH i s transcriptionally up-regulated by chorionic gonadotropin via cyclic AMP-i nduced androgen formation in the Leydig cell. It has ATPase and RNA helicas e activities and increases translation in vitro. This helicase is highly ex pressed in rat, mouse, and human testes and weakly expressed in the pituita ry and hypothalamus. GRTH is produced in both somatic (Leydig. cells) and g erminal (meiotic spermatocytes and round haploid spermatids) cells and is d evelopmentally regulated. GRTH predominantly localized in the cytoplasm may function as a translational activator. This novel helicase could be releva nt to the control of steroidogenesis and the paracrine regulation of androg en-dependent spermatogenesis in the testis.