DA1 和SMO2 基因在玉米生长发育中的功能

   DA1是控制种子器官大小的负调控因子，而且受ABA的诱导表达，其突变体的种子变大。SMO2 控制器官大小的正调控因子，突变体地上部变小，根系变短。这两个基因的发现和功能分析都是在拟南芥中进行的。目前，有关这两个基因功能的研究在单子叶植物中还未见报道。玉米作为我国最重要的粮食作物之一和典型的C4类模式植物，在农业生产和单子叶植物功能基因组学研究中具有重要地位。随着水土资源的日益紧张和粮食需求的日益增加，粮食安全问题日益突突。如何提高农作物的产量，是我国迫切需要解决的重大问题。从作物自身的遗传入手，解析影响产量形成的遗传因子及其作用分子机理，是进行农作物产量遗传改良的重要基础。本文拟从影响器官大小的基因DA1和SMO2入手，来研究这两个基因对玉米生长发育和产量的影响，为玉米产量的遗传改良提供候选目的基因。目前，我们已经通过生物信息学的方法解析得到玉米的这两个基因序列，为下一步基因克隆和研究它们的功能奠定了基础。

参考文献

Hu Z, Qin Z, Wang M, Xu C, Feng G, Liu J, Meng Z, Hu Y. The Arabidopsis SMO2, a homologue of yeast TRM112, modulates progression of cell division during organ growth.. Plant J. 2010,61(4):600-10.

Hu Z, Zhang X, Qin Z, Hu Y.Arabidopsis SMO2 regulates seed germination and ABA response.Plant Signal Behav. 2010,5(3):325-7.

Li Y, Zheng L, Corke F, Smith C, Bevan MW.Control of final seed and organ size by the DA1 gene family in Arabidopsis thaliana.Genes Dev. 2008,22(10):1331-6.

Weng J, Gu S, Wan X, Gao H, Guo T, Su N, Lei C, Zhang X, Cheng Z, Guo X, Wang J, Jiang L, Zhai H, Wan J. Isolation and initial characterization of GW5, a major QTL associated with rice grain width and weight.Cell Res. 2008,18(12):1199-209.

Krizek BA. Making bigger plants: key regulators of final organ size.Curr Opin Plant Biol. 2009, 12(1):17-22.

Shomura A, Izawa T, Ebana K, Ebitani T, Kanegae H, Konishi S, Yano M. Deletion in a gene associated with grain size increased yields during rice domestication. Nat Genet. 2008, 40(8):1023-8.

Song XJ, Huang W, Shi M, Zhu MZ, Lin HX. A QTL for rice grain width and weight encodes a previously unknown RING-type E3 ubiquitin ligase. Nat Genet. 2007,39(5): 623-30.

Bögre L, Magyar Z, López-Juez E. New clues to organ size control in plants. Genome Biol. 2008, 9(7): 226.

Marie C. Schruff, Melissa Spielman, Sushma Tiwari, Sally Adams, Nick Fenby and Rod J. Scott. The AUXIN RESPONSE FACTOR 2 gene of Arabidopsis links auxin signalling, cell division, and the size of seeds and other organs. Dvelopment 133, 251-261.

Beatrix M Horváth, Zoltán Magyar, Yuexing Zhang et al. EBP1 regulates organ size through cell growth and proliferation in plants.The EMBO Journal (2006) 25, 4909–4920

Elena Anastasiou, Sabine Kenz, Moritz Gerstung, Daniel MacLean, Jens Timmer, Christian Fleck, and Michael Lenhard .Control of Plant Organ Size by

KLUH/CYP78A5-Dependent Intercellular Signaling. Developmental Cell 13, 843–856, December 2007

Sabine Disch, Elena Anastasiou, Vijay K. Sharma, Thomas Laux, Jennifer C. Fletcher, and Michae Lenhard. The E3 Ubiquitin Ligase BIG BROTHER Controls Arabidopsis Organ Size in a Dosage-Dependent Manner. Current Biology 16, 272–279.

Beth A Krizek. Making bigger plants: key regulators of final organ size. Current Opinion in Plant Biology 2008, 12:1–6.

Gwyneth C Ingram and Richard Waites.Keeping it together: co-ordinating plant growth.Current Opinion in Plant Biology 2006, 9:12–20.

玉米脱水素基因在逆境应答中的功能研究

     植物脱水素基因在逆境应答过程中具有重要功能。作者通过生物信息学解析得到一个新的玉米脱水素基因序列，位于4号染色体的BAC克隆AC203943.3中。序列分析表明，它与小麦的COR410同源，在基因上有调控序列中存在ABA、AUXIN、茉莉酸甲酯的应答元件，以及冷胁迫和干旱胁迫应答元件。本课题拟通过表达谱分析、等位变异分析和转基因研究，探讨这个脱水素基因在玉米逆境应答中的功能，为玉米的抗逆分子育种提供分子标记和候选目的基因。

参考文献

Close, T. J. (1997). Dehydrins: a commonalty in the response of plants to dehydration and low temperature. Phsiologia Plantarum 100, 291-296.

Close, T.J., Choi, D-W., Campbell, S.A., Koag, M-C., Zhu, B.L. (1999). The dehydrin multigene family in the Triticeae and Maize(review). UCR, Riverside, CA

Danyluk , J et al.(1998).Accumulation of an Acidic Dehydrin in the Vicinity of the Plasma Membrane during Cold Acclimation of Wheat. The Plant Cell, 10, 623–638.

Rorat, T. (2006). Plant dehydrins- tissue location , structure and function.Cellular. and  Molecular Biology Letters, 11, 536 – 556.

 三个玉米SnRK2新基因的功能研究

  植物SnRK2基因在ABA信号转导、干旱渗透胁迫、矿质营养吸收及生长发育过程中具有重要功能。作者通过生物信息学分析，发现了三个新的玉米SnRK2基因， 与王国英课题组报道的不同。这三个新基因分别与拟南芥的SnRK2.2、SnRK2.4、SnRK2.6/OST1同源。本课题拟通过基因表达调控研究（不同逆境下的表达谱分析、亚细胞定位、启动子分析）和转基因研究，探讨这三个玉米新基因在生长发育、逆境应答中的功能，为玉米的抗逆分子育种提供候选目的基因。

参考文献

李利斌，刘开昌，李现刚，三个新的玉米SnRK2基因的鉴定和特征分析。山东农业科学，2009，12；7-11。

Fujita Y, Nakashima K, Yoshida T et al. Three SnRK2 protein kinases are the main positive regulators of abscisic acid signaling in response to water stress in Arabidopsis. Plant Cell Physiol. 2009, 50(12):2123-32.

Zheng Z, Xu X, Crosley RA et al. The protein kinase SnRK2.6 mediates the regulation of sucrose metabolism and plant growth in Arabidopsis. Plant Physiol. 2010,153(1):99-113

Nakashima K, Fujita Y, Kanamori N et al. Three Arabidopsis SnRK2 protein kinases, SRK2D/SnRK2.2, SRK2E/SnRK2.6/OST1 and SRK2I/SnRK2.3, involved in ABA signaling are essential for the control of seed development and dormancy. Plant Cell Physiol. 2009,50(7):1345-63.

Hirayama T, Umezawa T. The PP2C-SnRK2 complex: the central regulator of an abscisic acid signaling pathway. Plant Signal Behav. 2010, 5(2):160-3.

Vlad F, Rubio S, Rodrigues A et al. Protein phosphatases 2C regulate the activation of the Snf1-related kinase OST1 by abscisic acid in Arabidopsis. Plant Cell. 2009, 21(10):3170-84.

Huai J, Wang M, He Jet al. (2008). Cloning and characterization of the SnRK2 gene family from Zea mays. Plant Cell Report 27:1861–1868.

Kobayashi Y, Yamamoto S, Minami H et al. (2004). Differential activation of rice sucrose nonfermenting 1-related protein kinase2 family by hyperosmotic stress and abscisic acid. Plant Cell 16:1163-1177.

Mustilli AC, Merlot S, Vavasseur A et al. (2002). Arabidopsis OST1 protein kinase mediates the regulation of stomatal aperture by abscisic acid and acts upstream of reactive oxygen species production. Plant Cell 14: 3089–3099.

Melotto M, Underwood W, Koczan J et al. (2006). Plant stomata function in innate immunity against bacterial invasion. Cell 126:969–980.

Zou H, Zhang X, Zhao J R et al. 2006. Cloning and characterization of maize ZmSPK1, a homologue to nonfermenting1-related protein kinase2. African Journal of Biotechnology, 5, 490-496.

玉米SOS2/CIPK24和CIPK3的功能

植物的CIPK/SnRK3基因在植物逆境应答（干旱、低温、盐碱、淹水）、矿质营养吸收、生长发育及钙信号传导过程中具有重要功能。我们通过生物学信息学分析，发现了两个玉米的CIPK基因，分别与拟南芥和水稻的SOS2/CIPK24及CIPK3同源，与最近陈析丰等（Chen et al., 2011）报道的不同。本课题拟研究这两个基因在逆境应答（盐胁迫、低温胁迫）中的功能及对玉米生长发育的影响。

参考文献：

Chen X, Gu Z, Xin D, Hao L, Liu C, Huang J, Ma B, Zhang H. Identification and characterization of putative CIPK genes in maize. J Genet Genomics. 2011, 38(2):77-87.

Coello P, Hey SJ, and Halford NG. The sucrose non-fermenting-1-related (SnRK) family of protein kinases: potential for manipulation to improve stress tolerance and increase yield. J. Exp. Bot., 2011; 62(3): 883- 893.

Kim, K.N., Cheong, Y.H., Grant, J.J. et al. (2003). CIPK3, a Calcium sensor–associated protein kinase that regulates abscisic acid and cold signal transduction in Arabidopsis. Plant Cell 15:411–423

Liu, J., Ishitani, M., Halfter, U. et al. (2000). The Arabidopsis thaliana SOS2 gene encodes a protein kinase that is required for salt tolerance. Proc Natl Acad Sci USA 97:3730–3734

Luan S, Lan W, Chul Lee S. Potassium nutrition, sodium toxicity, and calcium signaling: connections through the CBL-CIPK network. Curr Opin Plant Biol. 2009,12(3): 339-46.

Pandey, G.K., Granta, J.J., Cheonga, Y.H. et al. (2008). Calcineurin-B like Protein CBL9 interacts with target kinase CIPK3 in the regulation of ABA response in seed germination. Molecular Plant 1:238–248

Pandey, G.K. (2008). Emergence of a novel calcium signaling pathway in plants: CBL-CIPK signaling network. Physiol Mol Bio Plants 14: 51–68

Xiang, Y., Huang, Y., Xiong, L. (2007). Characterization of stress-responsive CIPK genes in rice for stress tolerance improvement. Plant Physiol 144:1416–1428