Pentatricopeptide Repeat Proteins in Cotton.

Pentatricopeptide repeat (PPR) proteins are encoded by genes from one of the largest families in plants. PPR proteins are translocated to mitochondria or chloroplasts and play a broad role including RNA processing, fertility restoration in cytoplasmic male sterility, embryogenesis, and plant development. In this study, several recently sequenced cotton genomes were analyzed to identify PPR protein-coding genes for a phylogenetic and comparative structural genomic analysis. Single nucleotide polymorphisms (SNPs) were further identified for all the homologous PPR protein-coding genes. A genomewide gene expression study will be performed to reveal their regulations associated with abiotic and biotic stresses and male fertility.