| With the completion of the model plant Arabidopsis genome sequencing in 2000, the emphasis of the life science has been into the functional genomics. In this dissertation we focused on the function of genes associated with anther and pollen development including map-based cloning of Arabidopsis genes from male sterile mutants.From 19 Arabidopsis male sterile lines isolated from an ethyl methanesulphonate-induced (EMS-induced) population, a total of four male sterile mutants were screened with each mutant controlled by a single recessive gene. Cross-section of these male sterile mutant anthers showed that there is no pollen formation in ms157 anther while msl88 anther contains a few pollen grains with pollen shape distorted and reduced cytoplasmic content. However, pollen was formed in both anthers of ms115 and ms214.In order to isolate these genes, we established a set of molecular markers for the first-pass mapping of Arabidopsis genes. Of the 24 InDel markers, a total of 18 were developed in this work. The mutated genes ms157, ms188, msl 15 and ms214 were mapped on chromosome IV, V, V, I, respectively, using the molecular markers developed above. This set of molecular markers is stable, and easy to use. They are also used for other gene mapping in Arabidopsis.The ms188 gene was finely mapped. A total of 8 new InDel markers were designed to map msl88 using a segregating population with a total of 2135 male sterile progenies. MS188 was finally mapped to a region of 95.8kb between the molecular marker MDA7 and K24C1. There are a total of 28 genes in this region including a transcription factor AtMYB103.PCR method was used to identify candidate MS 188. Sequence analysis indicated that a point mutation occurred in the second exon of the AtMYB103 gene in male sterile mutant with CAA(Gln) replaced by a stop codon TAA. Thus, we believe that AtMYB103 is the candidate gene for MS 188. The genetic complementation and gene function analysis are being undertaken.
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