COPII genes <i>SEC31A</i> <i>/</i> <i>B</i> are essential for gametogenesis and interchangeable in pollen development in <i>Arabidopsis</i>

In eukaryotes, coat protein complex II (COPII) vesicles mediate anterograde traffic from the endoplasmic reticulum to Golgi apparatus. Compared yeasts, plants have multiple COPII proteins; however, functional diversity among them is less well understood. SEC31A and SEC31B are outer proteins found in Arabidopsis. this study, we explored function of compared it with that various perspectives. was widely expressed, but at a significantly lower level than SEC31B. SEC31A-mCherry SEC31B-GFP exhibited high co-localization rate pollen, growing pollen tubes. The sec31a single mutant normal growth. expression driven by promoter rescued abortion infertility observed sec31b. A sec31asec31b double unavailable due lethality gametophyte. Transmission electron microscopy revealed one quarter male gametogenesis arrested uninuclear microspore stage, while confocal laser scanning showed 1/4 female gametophyte development suspended megaspore stage sec31a-1/+sec31b-3/+ plants. Our study highlights essential role SEC31A/B their interchangeable functions development.