Functions of PPR Proteins in Plant Growth and Development

Abstract

Pentatricopeptide repeat (PPR) proteins form a large protein family in land plants, with hundreds of different members in angiosperms. In the last decade, a number of studies have shown that PPR proteins are sequence-specific RNA-binding proteins involved in multiple aspects of plant organellar RNA processing, and perform numerous functions in plants throughout their life cycle. Recently, computational and structural studies have provided new insights into the working mechanisms of PPR proteins in RNA recognition and cytidine deamination. In this review, we summarized the research progress on the functions of PPR proteins in plant growth and development, with a particular focus on their effects on cytoplasmic male sterility, stress responses, and seed development. We also documented the molecular mechanisms of PPR proteins in mediating RNA processing in plant mitochondria and chloroplasts.

Identification of Glu-D1 Alleles and Novel Marker–Trait Associations for Flour Quality and Grain Yield Traits under Heat-Stress Environments in Wheat Lines Derived from Diverse Accessions of Aegilops tauschii

“…Under heat-stress conditions (MED18/18), the marker rs3026863|F|0-12 on chromosome 2D was found to control the grain yield. The candidate genes of this marker encoded pentatricopeptide (PPR) proteins, which have been reported to be important in regulating plant growth, development, cytoplasmic male sterility, stress responses, and seed development [ 85 ]. The expression of this gene was not close to Glu-D1 .…”

Genome-Wide Association Study for Agro-Morphological Traits in Eggplant Core Collection

“…In this study, a total of 51 SNPs were associated with days to maturity, and one SNP was located in a gene that codes for pentatricopeptide repeat-containing protein (PPR). Mutations in these PPR protein-coding genes lead to the dysfunction of mitochondria and/or chloroplasts, thereby resulting in growth retardation, pollen abortion, and seed development defects in plants [ 63 ], indicating the important roles of PPR proteins in plant growth and development [ 64 ]. As presented in Table 6 , some of the highly significantly associated SNPs with days to maturity were found in genes that encode DNA ligase 4 (LIG4) (Ch03 at 2.5 Mbp), PPL1 PsbP-like protein 1 chloroplastic (Ch03 at 8.8 Mbp), 4-coumarate--CoA ligase-like 5 (4CLL5) (Ch05 at 3.8 Mbp), Actin-7 (Ch05 at 4.0 Mbp), PHYC Phytochrome C (Ch07 at 126.0 Mbp), and PAL5 phenylalanine ammonia-lyase.…”

Comparison of Mitochondrial Genomes between a Cytoplasmic Male-Sterile Line and Its Restorer Line for Identifying Candidate CMS Genes in Gossypium hirsutum

“…Most reported restorer-of-fertility ( Rf ) genes that counteract male sterility encode members of the pentatricopeptide repeat (PPR) family; these include petunia Rf [ 50 ], Brassica napus Rfk1 [ 51 ], Rahanus stivus Rfo [ 52 ], rice Rf1 [ 53 ], sorghum Rf1 [ 54 ], and others. Most PPR proteins localize to the mitochondria and chloroplasts and play important roles in post-transcriptional regulation within those organelles, mainly in RNA splicing, RNA cleavage, RNA editing, and RNA stabilization [ 55 , 56 ]. For example, the PPR protein, Rf6, is known to function with OsHXK6 to promote processing of the atp6–orfH79 transcript and restore fertility in rice [ 57 ], while OTP43 is essential for trans -splicing of nad1 intron 1 in Arabidopsis thaliana [ 58 ].…”