RT Journal Article SR Electronic T1 The PELOTA-HBS1 Complex Orchestrates mRNA Translation Surveillance and PDK1-mediated Plant Growth and Development JF bioRxiv FD Cold Spring Harbor Laboratory SP 2021.01.11.426208 DO 10.1101/2021.01.11.426208 A1 Wei Kong A1 Shutang Tan A1 Qing Zhao A1 De-Li Lin A1 Zhi-Hong Xu A1 Jiří Friml A1 Hong-Wei Xue YR 2021 UL http://biorxiv.org/content/early/2021/01/11/2021.01.11.426208.abstract AB The quality control system for messenger RNA is fundamental for cellular activities in eukaryotes. To elucidate the molecular mechanism of 3’-Phosphoinositide-Dependent Protein Kinase1 (PDK1), an essential regulator throughout growth and development of eukaryotes, a forward genetic approach was employed to screen for suppressors of the loss-of-function T-DNA insertional pdk1.1 pdk1.2 double mutant in Arabidopsis. Notably, the severe growth attenuation of pdk1.1 pdk1.2 is rescued by sop21 (suppressor of pdk1.1 pdk1.2) that harbours a loss-of-function mutation in PELOTA1 (PEL1). PEL1 is a homologue of mammalian PELOTA and yeast DOM34, which form a heterodimeric complex with the GTPase HBS1, responsible for ribosome rescue to assure the quality and fidelity of mRNA molecules. Genetic analysis further reveals that the dysfunction of PEL1-HBS complex fails to degrade the T-DNA-disrupted, truncated but functional PDK1 transcripts, thus rescuing pdk1.1 pdk1.2. Our studies demonstrate the functionality and identify the essential functions of a homologous PELOTA-HBS1 complex in higher plant, and provide novel insights into the mRNA quality control mechanism.