Transcriptional Profiling of the Downstream Genes of Sub1A-1 in Rice under Submergence

• Main Authors: Yu-Lin Wu, 吳育伶
• Other Authors: 施明哲
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/81991037946154380210

碩士 === 國立臺灣大學 === 植物科學研究所 === 102 === Sub1A-1, an ethylene response transcription factor (ERF), is up-regulated by ethylene and helps plants'' survival under submergence. Rice whose genotype carrying Sub1A-1 allele like FR13A and Pokkali (both of them are O. sativa ssp. indica cultivar) can tolerate prolonged submergence. The intolerant cultivars such as IR29 and IR64 possess Sub1A-2, and Swarna does not have Sub1A allele. However, the downstream genes under Sub1A-1 regulation remain to be investigated. By using FR13A, IR29 and Pokkali to do microarray analysis and further confirmed with Swarna, Swarna(Sub1), IR64 and IR64(Sub1), we validated several genes that were under Sub1A-1 regulation. There are 27 genes that were up-regulated by Sub1A-1 under submergence, including 9 transcription factors, 12 functional genes and 6 genes with unknown functions. On the other hand, there are only two genes with unknown function that were down-regulated by Sub1A-1. Among the genes that were up-regulated by Sub1A-1, 3 genes were involved in the glycolytic pathway, including Aldolase C-1, Glyceraldehyde-3-phosphate dehydrogenase (GAPC) and Pyruvate phosphate dikinase (PPDK). From the Electrophoretic mobility shift assay (EMSA) experiments, Sub1A-1 might directly regulate its downstream targets by binding to the GCC box on their promoters. The genes that are regulated by Sub1A-1 also contribute to the energy and metabolic adaption in plants. The ATP levels in Sub1 haplotypes such as FR13A and IR64(Sub1) were relative higher than IR29 and IR64. Sucrose was more abundant in IR64(Sub1) than IR64 after submergence. This indicated that the energy and carbohydrate reservation were important for survival under submergence.