Os03g0786400

zinc finger protein is an important class of eukaryotic transcription factors

Annotated Information

Function

The Cys-2/His-2-type (C2H2) zinc finger protein—also called a classical or TFIIIA-type zinc finger—that was first found in Xenopus oocytes is an important class of eukaryotic transcription factors[1]. The phytohormone cytokinin (CK) positively regulates the activity and function of the shoot apical meristem (SAM), which is a major parameter determining seed production. The rice (Oryza sativa L.) Gn1a/OsCKX2 (Grain number 1a/Cytokinin oxidase 2) gene, which encodes a cytokinin oxidase, has been identified as a major quantitative trait locus contributing to grain number improvement in rice breeding practice. The zinc finger transcription factor DROUGHT AND SALT TOLERANCE (DST) directly regulates OsCKX2 expression in the reproductive meristem. DST-directed expression of OsCKX2 regulates CK accumulation in the SAM and, therefore, controls the number of the reproductive organs[2]. And the zinc finger transcription factor can negatively regulate stomatal closure by direct modulation of genes related to H2O2 homeostasis. Loss of DST function increases stomatal closure and reduces stomatal density, consequently resulting in enhanced drought and salt tolerance in rice[3].

Expression

DST is located in the nucleus with transcriptional activation and it will express momentarily down under the condition of salt stress and osmotic stress, then recovered to pre-treatment levels. All transgenic plants overexpressing a wild-type DST allele (DSTREG1) showed reduced plant stature with less panicle branches and decreased grain number (Fig. S1 A–D). In contrast, the DST RNA interference (RNAi) transgenic plants showed increased panicle branches and enhanced grain number（Fig.S1E–H）.

Evolution

Generally, C2H2-type zinc finger proteins contain more than one zinc finger motif for DNA binding in the N terminus and separable transcriptional activation (or repression) domains in the C terminus [4]. The zinc finger motif is thought to recognize and bind its target DNA sequence, but has never been shown to be required for transcriptional activity [4,5,6].

Labs working on this gene

China Natl Hybrid Rice Res & Dev Ctr, State Key Lab Hybrid Rice, Changsha 410125, Hunan, Peoples R China.

Chinese Acad Sci, Shanghai Inst Biol Sci, Shanghai Inst Plant Physiol & Ecol, Natl Key Lab Plant Mol Genet, Shanghai 200032, Peoples R China.

References

[1] Miller J, McLachlan AD, Klug A(1985) Repetitive zinc-binding domains in the protein transcription factor IIIA from Xenopus oocytes. EMBO J 4:1609–1614.

[2] Shuyu Li;Bingran Zhao;Dingyang Yuan; Rice zinc finger protein DST enhances grain production through controlling Gn1a/OsCKX2 expression; Proceedings of the National Academy of Sciences, 2013, 110(8): 3167-3172

[3] Xin-Yuan Huang;Dai-Yin Chao; A previously unknown zinc finger protein, DST, regulates drought and salt tolerance in rice via stomatal aperture control; GENES & DEVELOPMENT, 2009, 23(15): 1805-1817

[4] Wolfe SA, Nekludova L, Pabo CO(2000) DNA recognition by Cys(2)His(2) zinc finger proteins. Annu Rev Biophys Biomol Struct 29:183–212.

[5] Sakamoto H, Maruyama K, Sakuma Y, Meshi T, Iwabuchi M, Shinozaki K, Yamaguchi-Shinozaki K(2004) Arabidopsis Cys2/His2-type zinc-finger proteins function as transcription repressors under drought, cold, and high-salinity stress conditions. Plant Physiol 136:2734–2746.

[6] Lin R, Ding L, Casola C, Ripoll DR, Feschotte C, Wang H(2007) Transposase-derived transcription factors regulate light signaling in Arabidopsis. Science 318:1302–1305.