22k microarray analysis on Zn-deficient rice

摘要

Zinc (Zn) is essential for all organisms, including plants. Zn deficiency causes physiological stress via the dysfunction of several enzyme systems and other metabolic functions in which Zn participates. To elucidate the molecular mechanisms affectedby Zn deficiency, we performed microarray analysis with Zn-deficient and Zn-sufficient rice. The genes up-regulated by Zn deficiency include the novel Zn transporter (OZT), nicotianamine synthase (NAS), PR-protein, starch synthase, and S-tike ribonuclease. OZT complemented a Zn uptake-deficient yeast mutant and was expressed in phloem cells of a Zn deficient plant. The expression of OsNAS3 and OsNAATl was dramatically increased in Zn-deficient shoots, indicating that synthesized phytosiderophores are involved in the transport of Zn within the plant. In addition, starch accumulation was observed hi Zn-deficient rice roots and shoots, corresponding to gene expression. Increase of ribonuclease activity was also observed hi Zn-deficient rice, but the ribonuclease up-regulated by Zn deficiency lacked the histidine residue essential for ribonucleic activity.