PAT mRNA decapping factors function specifically and redundantly during development in Arabidopsis

Abstract

Evolutionarily conserved PAT1 proteins activate mRNA decay through binding mRNA and recruiting decapping enzymes and other factors hence optimize transcriptional reprogramming during development. Here, we generated multiple mutants of pat1 (Protein Associated with Topoisomerase II), path1 and path2 and inspected their growth and leaf morphology phenotype. pat triple mutants exhibit extreme stunted growth and all mutants with pat1 exhibit leaf serration while mutants with pat1 and path1 all display short petioles. All 3 PATs can be found localized to Prossessing Bodies (PBs) upon auxin treatment and RNA-seq analysis indicate that all 3 PATs redundantly regulate auxin responses. Moreover, shade avoidance and NAC genes are misregulated in pat1path1 double and pat triple mutants suggesting PAT1 and PATH1 function in petiole elongation and leaf patterning. In conclusion, PAT proteins exhibit both specific and overlapping functions during different stages of plant growth and our observations underpin the importance of the mRNA decay machinery for proper development.