Figure 5.

Hypothetical schematic of sperm head elongation in WT and Cib4^–7/−7 mice. During the elongation of sperm heads, manchette compresses the caudal region both in WT and Cib4^–7/−7 mice. In the later stage of elongating spermatids, hook shapes are formed with F-actin bundles in the apical region of the heads in WT mice; however, no hook shapes were formed in Cib4^–7/−7 mice.