Figure 2.

Synapsis and Axis Length

(A) Spermatocyte chromosome spreads of Smc1β^+/+, Smc1β^+/+,1a, Smc1β^−/−, and Smc1β^−/−,1a mice, stained with anti-SYCP3 (red) for AEs/lateral elements (LEs) and with anti-SYCP1 (green) for SCs. Arrows indicate unsynapsed regions.

(B) Spermatocyte chromosome spreads of Smc1β^+/+, Smc1β^+/+,1a, Smc1β^−/−, and Smc1β^−/−,1a mice, stained with anti-SYCP3 (green) for AEs/LEs and anti-HORMAD1 (red) for unsynapsed region. Arrows indicate unsynapsed regions.

(C) Graphical representation of chromosome length (SYCP-stained) of spermatocyte spreads measured using ImageJ software. (n = 27, 7.111 μm [mean length; ±0.1153 μm SEM] Smc1β^+/+; n = 20, 7.388 μm [±0.1561 μm] Smc1β^+/+,1a; n = 15, 3.130 μm [±0.1235 μm] Smc1β^−/−; n = 22, 5.852 μm [±0.1756 μm] Smc1β^−/−,1a). According to Bonferroni’s multiple comparison test, all pairwise differences were statistically relevant (p < 0.05) except for the comparison of Smc1β^+/+ versus Smc1β^+/+,1a; scale bar, 5 μm; asterisks mark the XY chromosomes.

See also Figures S2, S3, and S7.