Towards a better molecular and physiological understanding of spikelet fertility in barley (Hordeum vulgare L.)

更好地了解大麦小穗育性的分子和生理学（Hordeum vulgare L.）

• 批准号: 251169880
• 负责人: Professor Dr. Thorsten Schnurbusch
• 金额: --
• 依托单位: Abteilung Züchtungsforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/251169880?language=en
• 关键词: Towards; better; molecular; physiological; understanding

This research proposal we will focus on the molecular elucidation of spikelet fertility in barley. It largely consists of two major parts: The first area of interest deals with the molecular analysis of a developmental mutant, six-rowed-spike2 (vrs2); whereas part two focuses on the molecular and physiological characterization of putative down-stream genes of Vrs4.1) Through genetic mapping we identified a vrs2-candidate chromosomal region containing two predicted gene models in the barley physical map. However, for the vrs2 locus only one known allele has been found so far (vrs2.e), which makes analysis of this locus difficult. Hence, we propose to search for, or create new vrs2 alleles using different genetic and molecular approaches. New alleles shall be found through (I) SANGER-sequencing of intermedium-barleys (H. vulgare convar. intermedium), and (II) TILLING analyses of the two candidate genes. (III) Putatively new alleles shall be tested for being allelic to vrs2.e. (IV) Transgenic approaches shall include a complementation of the vrs2.e mutant using the two wild type candidate genes; but similarly to create new alleles through TALEN technology. (V) Finally, vrs2.e and other putative alleles shall undergo a detailed phenotypic analysis as well as metabolic and hormonal profiling to reveal functional links to one of the two vrs2 candidate genes.2) In our very recent study (Koppolu et al. 2013)* we showed that Vrs4 regulates transcripts of genes belonging to the trehalose biosynthesis pathway. Trehalose-6-phosphate (T6P) has been implicated to control meristem determinacy and generally has been considered as an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. T6P levels are potentially governed by a group of trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) homologs. Here we would like to propose a detailed functional characterization of these two enzyme classes in barley inflorescences to elucidate their phylogenetic relationships, copy number, tissue-specificity, mRNA expression pattern and catalytic activities (i.e. TPS, ability to synthesize T6P; TPP, ability to dephosphorylate T6P).This research proposal aims at a deeper molecular, genetic and physiological insight into spikelet and floret fertility of barley for improving future yields of small grain cereals.

本研究拟对大麦小穗育性进行分子解析。它主要由两个主要部分组成：第一个感兴趣的领域涉及发育突变体六排穗2 （vrs2）的分子分析；通过遗传作图，我们在大麦物理图谱中发现了一个包含两个预测基因模型的vrs2候选染色体区域。然而，对于vrs2位点，迄今为止只发现了一个已知的等位基因(vrs2。E)，这使得对这个基因座的分析变得困难。因此，我们建议使用不同的遗传和分子方法寻找或创建新的vrs2等位基因。通过(1)对中大麦（H. vulgare convar）的sanger测序，可以发现新的等位基因。（II）对两个候选基因进行TILLING分析。（三）对推定的新等位基因进行与vrs2.e等位的检测。（四）转基因方法应包括vr2的补充。使用两个野生型候选基因的E突变体；同样通过TALEN技术创造新的等位基因。（五）最后，vrs2。E和其他可能的等位基因需要进行详细的表型分析以及代谢和激素分析，以揭示与两个vrs2候选基因之一的功能联系。2)在我们最近的研究(Koppolu et al. 2013)*中，我们发现Vrs4调节海藻糖生物合成途径的基因转录本。海藻糖-6-磷酸（T6P）与控制分生组织的确定性有关，通常被认为是一种重要的信号代谢产物，参与调节植物的生长和发育，以响应碳有效性。T6P水平可能受一组海藻糖-6-磷酸合成酶（TPS）和海藻糖-6-磷酸磷酸酶（TPP）同源物的控制。在此，我们希望对这两类酶在大麦花序中的功能进行详细的表征，以阐明它们的系统发育关系、拷贝数、组织特异性、mRNA表达模式和催化活性（即TPS，合成T6P的能力；TPP，去磷酸化T6P的能力）。本研究计划旨在对大麦的小穗和小花育性进行更深入的分子、遗传和生理研究，以提高未来小粒谷物的产量。