Abstract
Rice prolamin are composed of cysteine-poor (CysP) and cysteine-rich (CysR) molecules. CysP prolamins have micro-heterogeneity. esp1 mutation reduces the accumulation of CysP prolamins. To clear the genetic regulation mechanism for the synthesis and accumulation of CysP prolamin, Esp1 gene was isolated and the function was analyzed.
High-resolution linkage map was constructed by using the progeny of the cross between esp1 and "Kasalath". Esp1 gene was mapped within 20kb region on the map and five genes were predicted in the region. Sequencing analysis of genomic DNA indicated that single nucleotide in eRF1 coding region of esp1 mutant substituted. Complementation test, which transforms esp1 mutant with eRF1 gene of WT, demonstrated that the Esp1 gene encoded the eRF1. It is reported that eRF1 participates in the translation of the protein, suggesting that eRF1 in rice endosperm functions at the translation of CysP prolamin.
