Fine Mapping Of Genes In Rice White Stripe Mutant 6001 And Screening Of Candidate Gene

Rice leaf photosynthetic ability determines the biological yield and economic yield. The study of the mechanism of photosynthesis of rice leaf color mutants provides a theoretical basis for improving photosynthetic efficiency and cultivating high light efficiency rice varieties. The rice leaf color mutant has obvious traits and is widely used as an important material for functional genomics research. It is important to elucidate the molecular genetic mechanism of chlorophyll metabolism and pathogenesis. In this study, a leaf color mutant derived from indica rice variety 9311 was analyzed by trait analysis and map cloning. The results showed that:1 .The leaf color mutant is albino from the beginning of sowing,and the albino leaves were gradually turned into white and green stripes. white line and green fila arrayed orderly from leaf blade to midrib, Under low temperature conditions, the phenomenon of leaf whitening is more obvious. During the whole rice growth process,the white part of the leaf gradually decreased compared to the green part. Heading period until the wax cooked early, glume also appeared whitening phenomenon.2.The chlorophyll content was measured at the tillering and heading stages of the mutant 6001 and the wild type 9311. At the tillering stage, the chlorophyll a,chlorophyll b and carotene contents of the mutants were 50%, 65% and 52% of the normal materials,respectively. At the heading stage,the chlorophyll a,chlorophyll b and carotene contents of the mutant were 54%, 58% and 62% of the normal materials,respectively.3.Mutation gene mapping was performed on 200 implicit individuals of F2 with Japonica rice 02428 and mutant 6001. The gene was preliminarily mapped between the SSR marker RM136 and RM19715 of chromosome 6, And then further with white stripe mutant 6001/02428 hybrid F2 of 1300 strains of latent individual fine mapping,In the 6th chromosome design microsatellite (SSR) and Indel labeling of rice, 12 pairs of polymorphic markers were screened by constructing the near-isogenic pool. The results showed that the two markers closest to the target gene were Y27 and RM19732,respectively, and 9 and 1 recombinant individuals were detected. The molecular distance between the molecular markers is 75 kb and is separated from the label Y26.4.Using sequencing and bioinformatics analysis, it was found that there were 12 annotation genes in the region. The coding region of the gene LOC_Os06g 14620(ribonucleotide reductase small subunit), which contains the first initiation codon base,was found to have a total of 460 bp base deletion, In the initial codon upstream is also missing 134bp base, presumably stl allele. Although the coding region of the gene has a deletion of 460bp, there is still the presence of the start codon ATG and the stop codon TGA, which may only translate some of the functional proteins.