Akap4-knockout mice line was recently generating using CRISPR-Cas9 system by Fang and collaborators. 

The loss of AKAP4 led to abnormal sperm morphology, motility and infertility as previously described by Miki et al. 2008.

Their studies highlighted the Akap4's indispensable roles in the integrity of sperm flagellum and the step-wise maturation of spermatozoa within testis.

More details in the article

Fang X, Huang LL, Xu J, Ma CQ, Chen ZH, Zhang Z, Liao CH, Zheng SX, Huang P, Xu WM, Li N, Sun L (2019) Proteomics and single-cell RNA analysis of Akap4-knockout mice model confirm indispensable role of Akap4 in spermatogenesis. Developmental Biology. Vol 1606(19)30107-101. doi: 10.1016