Identification of Nucleus Sterility Candidate Genes using a Resequencing Technique in Sweet Pepper Sterile Line AB91

Abstract

Breeding hybrids with nuclear male sterile lines is an important method for the cross breeding of sweet peppers. To date, few reports have been published on the nuclear male sterility gene of sweet pepper. Yet, there are approximately 20 pepper nuclear male sterility lines in the world. Using the self-developed testing material, sweet pepper nuclear male sterile dual-purpose line AB91, the genome-wide resequencing technique was applied to firstly find that the mutation site causing the abortion of sweet pepper nuclear male sterility AB91 is on chromosome #5. The mutation gene Capana05g000747 was filtered out and validated by the flight mass spectrometry genotyping method and determined to be the gene causing the abortion of sweet pepper nuclear male sterility AB91. The gene Capana05g000747 contains eight exons and seven introns, and its mutation site is a non-synonymous mutation site located at the 6th exon; the base C mutated into A, and the amino acid changed from alanine to serine. Sequence alignment analysis showed that the gene Capana05g000747 has a similar function to gene At2g02148. The gene At2g02148 contains a pentatricopeptide repeat protein which has important physiological functions in the gene expression process of organelles and is closely related to the performance of male sterility genes. Therefore, Capana05g000747 was selected as an important candidate gene for sweet pepper nuclear male sterile testing material AB91.