Method for Identifying Indica-Japonica Rice by Using Specific Heat-Stable Protein Bands

Differential expression of heat-stable proteins in eighty-five cultivated rice(Oryza sativa L.)was analyzed by using SDS-PAGE and western blotting,to explore the feasibility of using specific proteins to identify Indica-Japonica rice.The results showed that the heat-stable proteins expressed differentially between Indica and Japonica rice,especially in the molecular weight of about 42-47kD range.Among them,45.2kD band(Band Ⅰ)and 46.5kD band(Band Ⅱ)were marker bands for typical Japonica rice.Both bands matched to Os03g0168100 in NCBI protein databank,42.0kD band(Band Ⅲ,matched to OsI_10172)was marker band for typical Indica rice.Eighty-five Indica and Japonica rice varieties were identified based on the expression pattern of these three bands,and then compared the results with Cheng's index.The concordances were 80.0% and 86.4% in typical Indica rice and Japonica rice,respectively.Therefore,the method of hest-stable protein marker bands can be used for identifying typical Indica rice and Japonica rice.