XVI International Botanical Congess
The lysine content of maize endosperm can be increased by the opaque2 (o2) mutation, which reduces prolamin synthesis and increases lysine-containing proteins. We showed that eEF-1A is increased in o2, furthermore, its concentration is correlated (r= 0.9) with lysine content. To understand the basis of this relationship and determine if eEF-1A content is heritable, we analyzed progeny from crosses of high and low eEF-1A genotypes. Continuous segregation was observed in the F2, suggesting multiple loci regulate this trait. eEF-1A is encoded by 12 genes, four are expressed in endosperm and two account for 75% of the transcripts. We identified three forms of eEF-1A protein in endosperm tissue, and we are purifying them to determine if specific isoforms are increased in o2.