Distribution of Sertoli cell microtubules, microtubule‐dependent motors, and the Golgi apparatus before and after tight junction formation in developing rat testis

Abstract

Sertoli cells are polarized epithelial cells of the seminiferous epithelium which provide structural and physiological support for differentiating germ cells. They establish different basal and adluminal environments for the selective nurturing of pre- and post-meiotic germ cells within the seminiferous epithelium, segregated by the Sertoli-Sertoli cell tight junctional complex, the blood-testis barrier. Tight junction formation between epithelial cells in vitro is a critical polarizing event associated with changes in polarized targeting of membrane-specific proteins and reorganization of microtubules, centrioles, and the Golgi apparatus. To investigate whether tight junction formation is associated with organelle reorganization in Sertoli cells in vivo, we have characterized distribution patterns of Sertoli cell microtubules, the mechanoenzymes kinesin and cytoplasmic dynein, and the Golgi apparatus during tight junction formation in developing rat testis. Immunocytochemistry on samples taken at 5, 10, 15, 20, and 25 days of age was used to examine the distribution of these proteins during the extensive cellular reorganization that culminates in the formation of the blood-testis barrier at 19 days of age. Our data show that the distribution patterns reflect the extensive intercellular repositioning of tubule cells in developing seminiferous tubules, but that changes in intracellular organization are not temporally associated with formation of the blood-testis barrier.

Vitamin C mitigates heat damage by reducing oxidative stress, inducing HSP expression in TM4 Sertoli cells

“…Microtubules are components of the cytoskeleton, it is the fundamental unit of the spindle that is required for mitotic and meiotic cell division (Helmke, Heald, & Wilbur, ). Sertoli cell microtubule networks are likely to be required for the transport of cargoes through the extensive cytoplasm that in turn are needed for normal cellular function and the ability to support the germ cell development (Neely, ; Redenbach & Boekelheide, ). During sperm release phase, the microtubules around the nucleus and in the cytoplasm have a role in maintaining Sertoli cell structural integrity.…”

Dynein 1 supports spermatid transport and spermiation during spermatogenesis in the rat testis

“…These findings are consistent with the concept that these MT-specific motor proteins and MT-based tracks are crucial to support these cellular events (12,22,65). Studies performed almost two decades ago have reported the presence of MT-based motor proteins dynein and kinesin II (Note: dynein and kinesin are minus-end-and plus-end-directed MT motor proteins, respectively) in the rodent testis, closely associated with the plus end (i.e., fast-growing end) of MTs at the Sertoli cell ES (31,60,71). Interestingly, the plus-end MTs are predominantly found near the basement membrane of the tubules but are also localized along MTs that stretch across the seminiferous epithelium (85,86,90).…”

Glycerol Disrupts Tight Junction—Associated Actin Microfilaments, Occludin, and Microtubules in Sertoli Cells

“…Several lines of evidence suggest that actin microfilament bundles are intimately involved with tight junction complexes between neighboring Sertoli cells (Amlani and Vogl, 1988;Boekelheide, et al, 1989;Vogl, 1989). The assembly of microfilament networks closely parallels the formation of tight junction complexes of the blood-testis barrier (Redenbach et al, 1995). Actin filament bundles occur adjacent to junctional networks and are seen to form a belt that circumscribes the base of each Sertoli cell (Vogl and Soucy, 1985;Vogl, 1989) and to undergo organizational changes during spermatogenesis (Vogl and Soucy, 1985;Amlani and Vogl, 1988).…”