title: Expression of a gene encoding a rice RING zinc-finger protein, OsRZFP34, enhances stomata opening.
abstract: By oligo microarray expression profiling, we identified a rice RING zinc-finger protein (RZFP), OsRZFP34, whose gene expression increased with high temperature or abscisic acid (ABA) treatment. As compared with the wild type, rice and Arabidopsis with OsRZFP34 overexpression showed increased relative stomata opening even with ABA treatment. Furthermore, loss-of-function mutation of OsRZFP34 and AtRZFP34 (At5g22920), an OsRZFP34 homolog in Arabidopsis, decreased relative stomata aperture under nonstress control conditions. Expressing OsRZFP34 in atrzfp34 reverted the mutant phenotype to normal, which indicates a conserved molecular function between OsRZFP34 and AtRZFP34. Analysis of water loss and leaf temperature under stress conditions revealed a higher evaporation rate and cooling effect in OsRZFP34-overexpressing Arabidopsis and rice than the wild type, atrzfp34 and osrzfp34. Thus, stomata opening, enhanced leaf cooling, and ABA insensitivity was conserved with OsRZFP34 expression. Transcription profiling of transgenic rice overexpressing OsRZFP34 revealed many genes involved in OsRZFP34-mediated stomatal movement. Several genes upregulated or downregulated in OsRZFP34-overexpressing plants were previously implicated in Ca(2+) sensing, K(+) regulator, and ABA response. We suggest that OsRZFP34 may modulate these genes to control stomata opening.
authors.affiliation: Department of Life Sciences, National Central University, Taoyuan, Taiwan.
authors.forename: Kuo-Hsuan
authors.initials: KH
authors.lastname: Hsu
authors.forename: Chia-Chin
authors.initials: CC
authors.lastname: Liu
authors.forename: Shaw-Jye
authors.initials: SJ
authors.lastname: Wu
authors.forename: Ying-Yu
authors.initials: YY
authors.lastname: Kuo
authors.forename: Chung-An
authors.initials: CA
authors.lastname: Lu
authors.forename: Ching-Rong
authors.initials: CR
authors.lastname: Wu
authors.forename: Pei-Jyun
authors.initials: PJ
authors.lastname: Lian
authors.forename: Chwan-Yang
authors.initials: CY
authors.lastname: Hong
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Ke
authors.forename: Juin-Hua
authors.initials: JH
authors.lastname: Huang
authors.forename: Ching-Hui
authors.initials: CH
authors.lastname: Yeh
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D003001:Cloning, Molecular; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018869:Heat-Shock Response / Q000235:genetics; D008969:Molecular Sequence Data; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D054046:Plant Stomata / Q000187:drug effects / Q000502:physiology*; D016415:Sequence Alignment; D013696:Temperature; D016335:Zinc Fingers
chemical_list: D010940:Plant Proteins; D000040:Abscisic Acid