ATG5 controls paternal mitochondrial elimination during spermatogenesis.

A study led by Professor Sun Mengxiang from the College of Life Sciences at Wuhan University has been published online in Nature Plants.

The paper, ATG5-HSP90.2-mediated micromitophagy as a cytological basis for maternal inheritance of plant mitochondria, reveals a novel mechanism by which angiosperms eliminate paternal mitochondria through a specialized process of mitochondrial micromitophagy.

This study confirms the existence of mitochondrial micromitophagy in plants and elucidates the detailed cytological process by which vacuoles engulf and degrade mitochondria through membrane invagination.

Results indicate that mitochondrial micromitophagy occurs in male germline cells and represents an evolved mechanism by which angiosperms eliminate paternal mitochondria.

The research indicates that mitochondrial micromitophagy is a conserved pathway for paternal mitochondrial elimination in angiosperms and has been optimized through evolution to suit the distinct characteristics of male germline cells across different plant groups.

The analysis of embryo development also explains how this intricate mechanism facilitates maternal inheritance of mitochondria and supports the normal transition of the zygote into an embryo post-fertilization.

This work bridges a long-standing gap in understanding the mechanism of paternal mitochondrial elimination in angiosperms through an interdisciplinary approach encompassing gametogenesis, micromitophagy, and cytoplasmic genetics.