Poster: Metabolic engineering

Abs # 291: Molecular cloning and expression analysis of the cell-wall invertase gene family of rice (Oryza sativa L.)

Presenter:	Cho, Jungil
Authors	Cho, Jungil  (A)   Lee, Sang-Kyu  (A)   Ko, Seho  (A)   Ryoo, Nayeon  (A)   Cho, Jiyoun  (A)   Lee, Youn-Hyeong  (A)   Bhoo, Seong Hee  (A)   Hahn, Tae-Ryong  (A)   Jeon, Jong-Seong  (A)
Affiliations:	(A): Plant Metabolism Research Center & Graduate School of Biotechnology

Cell-wall invertase (CIN) catalyzes the hydrolysis of sucrose into glucose and fructose for supplying carbohydrates to sink organs via an apoplastic pathway. To identify rice cell-wall invertase genes, we carried out systematic BLAST searches of the recently published sequence of the rice genome and identified eight putative cell-wall invertase genes, designated OsCIN 1, 2, 3, 4, 5, 6, 7 and pseudoOsCIN8. Expression of the genes was detected in various organs with specific patterns. In particular, four genes were expressed in immature seeds and the OsCIN3 expression was flower-specific. The transcript level of OsCIN1 was significantly increased by sucrose treatment, but OsCIN5 was down regulated. Expression of three genes, OsCIN1, 4, 5, was dramatically increased by blast infection. These results suggest that the OsCIN genes are regulated by various factors such as sucrose level and pathogen infection and act as an important component for supplying carbohydrates into various sink organs.