FIG. 3.

ubi-H2A marks the partially synapsed 1¹³ translocation bivalent of T/T′ spermatocytes. The top row shows four T/T′ pachytene spermatocyte spread nuclei stained with anti-ubi-H2A (green) and anti-Sycp3 (red). The closed arrowheads indicate the location of the 1¹³ bivalent, at different positions with respect to the XY body (open arrowheads). Bar, 20 μm. The images in the second row represent the four defined groups of 1¹³ synapsis morphologies, detected with anti-Sycp3 staining and shown at a higher magnification (bar, 5 μm). PR, partially synapsed rest; PA, partially synapsed A shape; PH, partially synapsed horseshoe shape; CS, complete synapsis. The table shows that an increasing fraction of 1¹³ bivalents is ubi-H2A negative when synapsis is more complete. Absolute numbers of scored nuclei with no ubi-H2A signal (−), a low ubi-H2A signal (+/−), or a clear ubi-H2A signal (+) are indicated. Tot, total number of nuclei counted.