Immunohistochemical analysis of the expression of two serine–threonine kinases in the maturing mouse testis

Previously we identified two intronless serine–threonine kinase genes (Tsk1 and Tsk2) located 3 kb apart on mouse chromosome 16 (Galili, N., Baldwin, H.S., Lund, J., Reeves, R., Gong, W., Wang, Z., Roe, B.A., Emanuel, B.S., Nayak, S., Mickanin, C., Budraf, M.L., Buck, C.A., 1997. A region of mouse chromosome 16 is syntenic to the DiGeorge, velocardiofacial syndrome minimal critical region. Gen. Res. 7, 17–26). Tsk1 was identical to a putative testicular kinase reported by Bielke et al. (Bielke, W., Blaschke, R.J., Miescher, G.C., Zurcher, G., Andres, A.C., Ziemiecki, A., 1994. Characterization of a novel murine testis-specific serine/threonine kinase. Gene 13, 235–239). Here we document the expression patterns of each Tsk throughout spermiogenesis showing an initial association of Tsk1 with cells in meiotic metaphase and a later association of Tsk2 with tail-like structures in the lumen of the seminiferous tubule.