Updated Progress on Group II Intron Splicing Factors in Plant Chloroplasts

Abstract

Group II introns are large catalytic RNAs (ribozymes) in the bacteria and organelle genomes of several lower eukaryotes. Many critical photosynthesis-related genes in the plant chloroplast genome also contain group II introns, and their splicing is critical for chloroplast biogenesis and photosynthesis processes. The structure of chloroplast group II introns was altered during evolution, resulting in the loss of intron self-splicing. Therefore, the assistance of protein factors was required for their splicing processes. As an increasing number of studies focus on the mechanism of chloroplast intron splicing; many new nuclear-encoded splicing factors that are involved in the chloroplast intron splicing process have been reported. This report reviewed the research progress of the updated splicing factors found to be involved in the splicing of chloroplast group II introns. We discuss the main problems that remain in this research field and suggest future research directions.

Chloroplast gene expression: Recent advances and perspectives

“…Besides this intron-coded MatK, many nucleus-encoded splicing factors have been identified that localize to the chloroplast, such as the RNase III-domain protein RNC1 of maize ( Watkins et al., 2007 ), the plant organelle RNA recognition protein what’s this factor (WTF1), also from maize ( Kroeger et al., 2009 ), and ACCUMULATION OF PHOTOSYSTEM ONE 1 from maize and Arabidopsis ( Watkins et al., 2011 ). A summary of chloroplast splicing factors can be found in several detailed reviews ( de Longevialle et al., 2010 ; Schmitz-Linneweber et al., 2015 ; Wang et al., 2022 ; Zeng et al., 2022 ).…”