Identification and Expression Analysis of Hypoxia Stress Inducible CCCH-type Zinc Finger Protein Genes in Rice

Flooding is one of the threatening abiotic stresses in recent global warming. In order to understand flooding-caused low oxygen stress response at molecular level, microarray-linked isolation of the hypoxia inducible genes were conducted. Seventeen genes that were up-regulated by the factor of more than 3 fold, were confirmed as hypoxia inducible. Among them, a CCCH-type zinc finger protein gene, OsCCCH-Zn-1, was further characterized due to its novelty as a hypoxia-inducible zinc finger gene as well as its significant induction by hypoxia stress. OsCCCH-Zn-1 was also up-regulated by submergence, ABA and drought stresses. In the normal growth condition, OsCCCH-Zn-1 was expressed in the flag leaf sheath, highest intemode and developing seeds. In rice, at least 12 CCCH-type zinc finger protein genes were retrieved by in silico analysis. Among these, we found that the zinc finger genes OsCCCH-Zn-1, -2, -6 were induced by hypoxia stress.