Figure 2
Intracellular distribution of the Merlin protein at various stages of spermatogenesis. In the control cyst, Merlin was detected in the cellular cortex of spermatocytes (A). In prometaphase (B) and metaphase (C) of meiosis, the cortical localization of Merlin became more evident. In telophase (D), Merlin redistributed and accumulated in the area associated with the microtubules of the central spindle. During cytokinesis (E), Merlin staining remained associated with the microtubules but was less intense in the region of the contractile ring. In the onion-stage spermatids (F), Merlin was highly concentrated in the Nebenkern. This localization pattern was maintained through the comet stage of spermatid elongation (G). The insert in panel G shows intense Merlin staining in the two subunits of Nebenkern in spermatids. In the control cyst, containing mature sperm, bright Merlin staining was also seen as a punctate dot in the acrosomal region (H). Merlin staining was still detected in the Mer3 cyst at the comet stage; however, sperm nuclei were scattered throughout the cyst, and the arrangement of spermatids was irregular (I).