Dissecting the mechanism of nuclear restitution in Arabidopsis male meiosis

Abstract

Meiosis is essential for the successful development of haploid germline cells. Recent studies on the Arabidopsis jason (jas) mutant revealed that an organelle band plays a key role in spindle separation during simultaneous cytokinesis. This study focused on a novel jas suppressor mutant, peleus (pel), which restores haploid pollen production in the jas background. PEL encodes a vacuole-localized protein that negatively regulates chromosome distance during metaphase II by modulating secretory trafficking. JAS, PEL, and the ubiquitin-like protein (UBQL) coordinate the delivery of proteins and membrane components to the organelle band. PEL and UBQL antagonistically inhibit the secretory trafficking driven organelle band formation. Our findings underscore the critical role of secretory trafficking in maintaining organelle band integrity and ensuring precise chromosome distance during meiosis II. This research provides new insights into the unreduced gametes formation and application in plant breeding.