Screening differential proteins in OsAAP6 different transgenic rice endosperms based on iTRAQ proteomics

【Objective】The purpose of the study was to screen the differential proteins in the endosperm of different OsAAP6 transgenic rice based on iTRAQ proteomics, and to clarify the differential proteins in the endosperm, in a bid to provide a theoretical basis for the future use of the OsAAP6 gene to enhance the nutritional quality of rice. 【Method】Using rice OsAAP6 overexpression positive OX(+) and negative control OX(-) materials, as well as OsAAP6 complementary expression positive ZpZc(+) and negative control ZpZc(-) experimental materials, the isotope marker relative and absolute quantification(iTRAQ) technology was used for proteomic detection and analysis. And the contents of four types of storage proteins(gluten, gliadin, albumin and globulin) in its endosperm was detected using the Coomassie brilliant blue G-250 method. 【Result】Compared with the ZpZc(-) and OX(-) transgenic negative control, the expression of OsAAP6 gene in ZpZc(+) and OX(+) transgenic positive endosperm was extremely significantly increased at P<0.01 and P<0.001 levels, respectively. Compared with the ZpZc(-) and OX(-) transgenic negative control, a total of 58 differential proteins were simultaneously up-regulated or down-regulated for expression in ZpZc(+) and OX(+) transgenic positive rice, of which 39 proteins significantly increased(P<0.05, the same below), and 19 proteins significantly decreased.Among the 39 co-up-regulated proteins, 27 proteins were involved in the synthesis and accumulation of rice seed storage substrates, and 16 up-regulated proteins were involved in the metabolism and accumulation of seed storage proteins.Compared with the ZpZc(-) and OX(-) transgenic negative control, the content of glutelin, gliadin, albumin and globulin in the endosperm of ZpZc(+) and OX(+) transgenic positive rice was significantly increased. 【Conclusion】Upregulation of the OsAAP6 gene expression can inhibit the accumulation of proteins related to amylopectin synthesis, but promote the accumulation of storage proteins in the endosperm, thereby increasing the content of gluten, gliadin, albumin and globulin in the endosperm. It can be used for molecular breeding and genetic improvement of new high protein rice varieties.