Figure 1.

HELLS is expressed by spermatogonia and spermatocytes in WT and Dicer1 cKO mice. (A) In stage II–V of WT mouse seminiferous epithelial cycle, HELLS (red) expression is restricted to spermatogonia (arrow). Sex bodies (arrowhead) in early-pachytene spermatocytes are positive for γH2AX (green). (B) In WT stages VII–VIII, HELLS is expressed in spermatogonia (arrow), preleptotene spermatocytes (asterisk) and mid-pachytene spermatocytes, where the signal concentrates to the γH2AX-positive sex bodies (arrowhead). (C) In WT stage IX a strong HELLS expression is maintained in leptotene spermatocytes (asterisk) and sex bodies (arrowhead) of late-pachytene spermatocytes. In Dicer1 cKO mice the expression pattern of HELLS is similar to WT in stages (D) I–IV, (E) VII–VIII and (F) IX. DAPI stains chromatin (white). Basement membrane of seminiferous epithelium (dotted line), spermatogonia (arrow), early spermatocytes (asterisk), sex body (arrowhead). Scale bars 10 µm.