TSKS concentrates in spermatid centrioles during flagellogenesis

Abstract

Centrosomal coiled-coil proteins paired with kinases play critical roles in centrosomal functions within somatic cells, however knowledge regarding gamete centriolar proteins is limited. In this study, the substrate of TSSK1 & 2, TSKS, was localized during spermiogenesis to the centrioles of post-meiotic spermatids, where it reached its greatest concentration during the period of flagellogenesis. This centriolar localization persisted in ejaculated human spermatozoa, while centriolar TSKS diminished in mouse sperm, where centrioles are known to undergo complete degeneration. In addition to the centriolar localization during flagellogenesis, mouse TSKS and the TSSK2 kinase localized in the tail and acrosomal regions of mouse epididymal sperm, while TSSK2 was found in the equatorial segment, neck and the midpiece of human spermatozoa. TSSK2/TSKS is the first kinase/substrate pair localized to the centrioles of spermatids and spermatozoa. Coupled with the infertility due to haploinsufficiency noted in chimeric mice with deletion of TSSK 1 & 2 (companion paper) this centriolar kinase/substrate pair is predicted to play an indispensable role during spermiogenesis.

Characterization, expression, and functional analysis of testis-specific serine/threonine kinase 1 (Tssk1) in the pen shellAtrina pectinata

“…Tssk1 and Tssk2 are expressed when spermatids differentiate into morphologically mature spermatozoa during spermiogenesis. This indicates the important roles of Tssk1 and Tssk2 in normal male reproduction (Xu et al 2008). Tssk3 is predominantly expressed in interstitial Leydig cells (Zuercher et al 2000).…”

“…Prior research reports that Tssk1 was found in mature spermatozoa, and many studies have shown that this gene plays an important role in mammalian spermatogenesis (Xu et al 2008). Tssk1 has been reported to be expressed in the testis of the bivalve mollusks, Argopecten purpuratus and Mytilus edulis, suggesting its role in spermatogenesis and/or sperm function in bivalves (Boutet et al 2008;Ciocan et al 2011).…”

Toward the identification of a subset of unexplained infertility: a sperm proteomic approach

“…In our study, the expression of TSSK2 was found at lower abundance in sperm that resulted in poor blastocyst development. This protein is localized to the centrioles during spermatogenesis and may be associated with dynamic changes in assembly of microtubule structures during spermatogenesis (17). Further, systematic mutation analysis of the TSSK2 gene in infertile men with azoospermia and severe oligozoopermia found a possible association of nucleotide variations in the TSSK2 gene and impaired spermatogenesis (18).…”

The role of chromatoid bodies and cytoskeleton in differentiation of rat spermatozoids

“…Mammalian spermatids differentiating into sper matozoids have three MT types: cytoplasmic, axoneme MTs growing from the distal centriole (Xu et al, 2008), and noncentrosomal manchette MTs (Tres and Kierzsenbaum, 1996;Fouquet et al, 1998;Mochida et al, 1998;Kierszenbaum, 2002;Kierszen baum and Tres, 2010;Kierszenbaum et al, 2011).…”