Analysis of gene expression in slpslp (stunted lemma and palea)rice inflorescence by DNA microarray

• Main Authors: Chia-Hao Kang, 康家豪
• Other Authors: Li-Fei Liu
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/57389992293070913547

碩士 === 臺灣大學 === 農藝學研究所 === 95 === The size and shape of lemma and palea can determine the rice grain size, and influence final yield of rice. In this study, a mutated rice induced by sodium azide, is used to study genes that regulate development of lemma and palea. This mutant has two different mutated phenotypes. The homozygous line shows stunned lemma and palea(slpslp), and heterozygous line shows small lemma and palea(SLPslp), which are only half in length compared to the normal one. Self-crossing of heterozygous line(SLPslp) can produce three different types of lemma/palea phenotype； one is normal(SLPSLP), another is SLPslp, and the other is slpslp. The segregation ratio is close to 1:2:1, which fits to single gene model according to the Mendel’s first law. To investigate the difference of gene expression between SLPSLP and slpslp, young inflorescences(< 5 mm) were collected and used for DNA microarray analysis. From DNA microarray result, 322 up-regulated genes and 92 down-regulated genes were obtained by screening the gene expression with over 2-fold chang between slpslp and SLPSLP inflorescences. The microarray result was confirmed by using Q-PCR of 6 genes in up-or down-regulated gene categories. Comparing both results from DNA microarray and cDNA-AFLP(Liu, 2003), it was found that only salT gene was consistently highly expressed in slpslp inflorescence. After annotation, there are 126 and 40 known genes up-regulated and down-regulated respectively. Furthermore, 126 up-regulated gene were classified into 18 groups, 40 down-regulated gene were classified into 9 groups. In this study, we focused on transcription factors(TF) and analysed their relationship among differentially expressed genes. As so far, it needs more evidence to proof this relationship. However, there are two genes, OsMADS55 and OsIAA9, inhibited and enhanced, respectively in slpslp inflorescence might have effects on lemma/palea development and are worth studying further. Therefore, we made a gene map that descripe the differential expression gene distributing on chromosomes. This map can help to realize the location on chromosome of the mutant gene.