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MRNA surveillance complex PELOTA-HBS1 regulates phosphoinositide-dependent protein kinase1 and plant growth.

ABSTRACT: The quality control system for messenger RNA (mRNA) is fundamental for cellular activities in eukaryotes. To elucidate the molecular mechanism of 3'-phosphoinositide-dependent protein kinase1 (PDK1), a master regulator that is essential throughout eukaryotic growth and development, we employed a forward genetic approach to screen for suppressors of the loss-of-function T-DNA insertion double mutant pdk1.1 pdk1.2 in Arabidopsis thaliana. Notably, the severe growth attenuation of pdk1.1 pdk1.2 was rescued by sop21 (suppressor of pdk1.1 pdk1.2), which harbors a loss-of-function mutation in PELOTA1 (PEL1). PEL1 is a homolog of mammalian PELOTA and yeast (Saccharomyces cerevisiae) DOM34p, which each form a heterodimeric complex with the GTPase HBS1 (HSP70 SUBFAMILY B SUPPRESSOR1, also called SUPERKILLER PROTEIN7, SKI7), a protein that is responsible for ribosomal rescue and thereby assures the quality and fidelity of mRNA molecules during translation. Genetic analysis further revealed that a dysfunctional PEL1-HBS1 complex failed to degrade the T-DNA-disrupted PDK1 transcripts, which were truncated but functional, and thus rescued the growth and developmental defects of pdk1.1 pdk1.2. Our studies demonstrated the functionality of a homologous PELOTA-HBS1 complex and identified its essential regulatory role in plants, providing insights into the mechanism of mRNA quality control.

SUBMITTER: Kong W

PROVIDER: S-EPMC8331137 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Structural basis for mRNA surveillance by archaeal Pelota and GTP-bound EF1? complex.

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2023-12-31 | GSE247328 | GEO

PELOTA and HBS1 suppress co-translational messenger RNA decay in Arabidopsis

Project description:This SuperSeries is composed of the SubSeries listed below.

2023-12-31 | GSE247330 | GEO

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