AUTHOR=Feng Xingxing , Yang Suxin , Zhang Yaohua , Zhiyuan Cheng , Tang Kuanqiang , Li Guang , Yu Hui , Leng Jiantian , Wang Qingyu 

TITLE=GmPGL2, Encoding a Pentatricopeptide Repeat Protein, Is Essential for Chloroplast RNA Editing and Biogenesis in Soybean

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.690973

DOI=10.3389/fpls.2021.690973

ISSN=1664-462X

ABSTRACT=<p>Chloroplast biogenesis and development are highly complex processes requiring interactions between plastids and nuclear genomic products. Pentatricopeptide repeat (PPR) proteins play an essential role in the development of chloroplasts; however, it remains unclear how RNA editing factors influence soybean development. In this study, a <italic>Glycine max pale green leaf 2</italic> mutant (<italic>Gmpgl2</italic>) was identified with decreased chlorophyll contents. Genetic mapping revealed that a single-nucleotide deletion at position 1949 bp in the <italic>Glyma.05g132700</italic> gene in the <italic>Gmpgl2</italic> mutant, resulting in a truncated GmPGL2 protein. The nuclear-encoded <italic>GmPGL2</italic> is a PLS-type PPR protein that localizes to the chloroplasts. The C-to-U editing efficiencies of <italic>rps16</italic>, <italic>rps18</italic>, <italic>ndhB</italic>, <italic>ndhD</italic>, <italic>ndhE</italic>, and <italic>ndhF</italic> were reduced in the <italic>Gmpgl2</italic> mutant. RNA electrophoresis mobility shift assay (REMSA) analysis further revealed that GmPGL2 binds to the immediate upstream sequences at RNA editing sites of <italic>rps16</italic> and <italic>ndhB in vitro</italic>, respectively. In addition, GmPGL2 was found to interact with GmMORF8, GmMORF9, and GmORRM6. These results suggest that GmPGL2 participates in C-to-U RNA editing <italic>via</italic> the formation of a complex RNA editosome in soybean chloroplasts.</p>