A mitochondrial protein associated with cytoplasmic male sterility in the T cytoplasm of maize

Abstract

Mitochondrial DNA in the T male-sterile cytoplasm (cms-T) of maize contains an open reading frame (ORF 13) associated with the T type of sterility. Antibodies raised to a chemically synthesized oligopeptide corresponding to ORF 13 were used to establish the expression of a 13-kDa protein from this reading frame. The 13-kDa polypeptide is synthesized uniquely in cms-T maize and purifies with the membrane fraction of T mitochondria. We assign the symbol urf13-T to designate this mitochondrial gene. Presence of the nuclear restorer gene Rf1 in cms-T plants results in a decrease in abundance of 13-kDa protein and alteration in the transcripts of urf13-T.