Autophagy core protein ATG5 is required for elongating spermatid development, sperm individualization and normal fertility in male mice.

Spermiogenesis is the longest phase of spermatogenesis, with dramatic morphological changes and a final step of spermiation, which involves protein degradation and the removal of excess cytoplasm; therefore, we hypothesized that macroautophagy/autophagy might be involved in the process. To test this hypothesis, we examined the function of ATG5, a core autophagy protein in male germ cell development. Floxed and mice were crossed to conditionally inactivate in male germ cells.