Expression profile of stages of seminiferous tubules, purifed germ cells and sertoli cells

Mammalian spermatogenesis is a complex biological process that occurs within a highly organized tissue, the seminiferous epithelium. The coordinated maturation of spermatogonia, spermatocytes and spermatids suggests the existence of precise programs of gene expression in these cells as well as in their neighboring somatic Sertoli cells. The objective of this study was to elucidate genes encoding the proteins that execute these programs. Rat seminiferous tubules at stages I, II-III, IV-V, VI, VIIa,b, VIIc,d, VIII, IX-XI, XII, XIII-XIV of the cycle were isolated by microdissection and Sertoli cells, spermatogonia plus early spermatocytes, pachytene spermatocytes and spermatids were purified from enzymatically-dispersed testes. Microarray analysis using Rat Genome 230 2.0 arrays identified a total of 16,971 probe sets that recognized transcripts. A comparison with the transcriptome of other tissues identified 398 testis-specific probe sets, which therefore are potential targets for the development of new contraceptives. Sequential waves of cell and stage-specific gene expression are associated with progression of germ cells through the stages of the cycle of the seminiferous epithelium and 1612 probe sets recognized transcripts whose expressions varied at least 4-fold across the stages of the cycle. Pathway analyses reveal that entire biological processes are regulated cyclically in testicular cells. Important among these are cell cycle and DNA repair. Thus, stage-specific gene expression is a widespread and fundamental characteristic of spermatogenic cells and Sertoli cells.

69

Johnston DS, Wright WW, Dicandeloro P, Wilson E, Kopf GS, Jelinsky SA