Molecular and genetic networks determining row number in cultivated barley.

决定栽培大麦行数的分子和遗传网络。

• 批准号: BB/K01613X/1
• 负责人: Robbie Waugh
• 金额: $ 46.34万
• 依托单位: James Hutton Institute
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FK01613X%2F1
• 关键词: Molecular; genetic; networks; determining; row

Wild barleys, the original domesticated forms and the majority of current elite UK cultivars produce two rows of grain bearing spikelets either side of the inflorescence, or spike. However, soon after the domestication, barleys with six rows of grain emerged that ultimately dominated early barley cultivation. Mutations in a single gene called SIX-ROWED SPIKE 1 (VRS1) have been identified as responsible for this important developmental switch. In two-rowed types, VRS1 mRNA is expressed in progenitor cells of the lateral spikelets which remain sterile presumably because VRS1 protein represses expression of genes that are required for development of 'lateral fertility'. Inactivating VRS1 via mutation would de-repress expression of lateral fertility genes, resulting in a six-rowed spike. While VRS1 is core to this process, we also know from historical studies with barley mutants that at least 11 different SIX-ROWED SPIKE genes influence the degree of fertility of the lateral spikelets. For example, we recently identified SIX-ROWED SPIKE 5 (VRS5), and showed that different versions of this gene (that we call 'alleles') are always paired with different versions of VRS1 in commercial two- and six- rowed barleys. This pairing is important because in lines that have the six-row version of VRS1 (denoted as vrs1), a two-row VRS5 allele (Vrs5) causes the development of small grain from the lateral spikelets. In contrast, the six-row version of VRS5 (vrs5) causes the lateral spikelets to develop fully, with important consequences on yield. This observation demonstrates that getting the correct combination of alleles at VRS genes is extremely important. While mutant studies have identified many VRS genes, we recently showed that natural variation in only four genes is associated with determining whether current elite UK barley cultivars are genetically optimal two- or six-row-types. As expected, one of these was VRS1 and another VRS5. We recently identified the third gene as VRS3 and are trying to identify the fourth, which does not coincide with the location of any of the eleven VRS mutants. In parallel, VRS4 has been identified by German collaborators. While we now know these genes are intrinsically linked by their involvement in the developmental pathway that restores fertility to a nascent floral organ (i.e. the lateral spikelets) at the moment we have no idea if or how these components interact, what other genes/proteins are involved or how six-rowed types evolved over the 10,000 years since the domestication of the species. These are the issues we plan to address in this project. We believe that a better understanding of this fundamental developmental process will provide insights into how we can exploit variation in genes controlling plant morphology and architecture to ultimately improve plant yield.

野生大麦、原始的驯化形式和大多数当前的英国精英品种在花序两边或穗状花序两边产生两排籽粒小穗。然而，在驯化后不久，出现了六行粒的大麦，最终主导了早期的大麦种植。一种名为六棱穗1号(VRS1)的基因的突变已被证实与这一重要的发育开关有关。在双棱型中，VRS1mRNA在保持不育的侧生小穗的祖细胞中表达，可能是因为VRS1蛋白抑制了‘侧生育性’发育所需的基因的表达。通过突变使VRS1失活会抑制侧向生育基因的表达，导致六排穗。虽然VRS1是这一过程的核心，但我们也从大麦突变体的历史研究中知道，至少有11个不同的六棱穗基因影响侧生小穗的育性程度。例如，我们最近发现了六棱穗5(VRS5)，并表明在商业两棱和六棱大麦中，该基因的不同版本(我们称之为‘等位基因’)总是与不同版本的VRS1配对。这种配对很重要，因为在具有六行VRS1(表示为Vrs1)的品系中，两行VRS5等位基因(Vrs5)导致从侧生小穗发育出小粒。相反，VRS5(Vrs5)的六行版本使侧生小穗发育充分，对产量有重要影响。这一观察表明，在VRS基因上获得正确的等位基因组合是极其重要的。虽然突变研究已经确定了许多VRS基因，但我们最近发现，只有四个基因的自然变异与决定当前英国优质大麦品种是遗传上最优的两行还是六行类型有关。不出所料，其中一个是VRS1，另一个是VRS5。我们最近确认了第三个基因是VRS3，并试图确定第四个基因，这与11个VRS突变体中的任何一个的位置都不一致。与此同时，VRS4已经被德国的合作者发现。虽然我们现在知道这些基因通过参与将生育能力恢复到新生的花器官(即侧生小穗)的发育途径而内在地联系在一起，但目前我们不知道这些成分是否或如何相互作用，还涉及哪些其他基因/蛋白质，或者自物种驯化以来的10,000年来六棱类型是如何进化的。这些都是我们计划在这个项目中解决的问题。我们相信，对这一基本发育过程的更好理解将为我们如何利用控制植物形态和结构的基因变异最终提高植物产量提供洞察力。

项目成果

Barley SIX-ROWED SPIKE3 encodes a putative Jumonji C-type H3K9me2/me3 demethylase that represses lateral spikelet fertility.

• DOI: 10.1038/s41467-017-00940-7
• 发表时间: 2017-10-16
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Bull H;Casao MC;Zwirek M;Flavell AJ;Thomas WTB;Guo W;Zhang R;Rapazote-Flores P;Kyriakidis S;Russell J;Druka A;McKim SM;Waugh R
• 通讯作者: Waugh R

BaRTv1.0: an improved barley reference transcript dataset to determine accurate changes in the barley transcriptome using RNA-seq

• DOI: 10.1186/s12864-019-6243-7
• 发表时间: 2019-12-11
• 期刊: BMC GENOMICS
• 影响因子: 4.4
• 作者: Rapazote-Flores, Paulo;Bayer, Micha;Simpson, Craig G.
• 通讯作者: Simpson, Craig G.

Interaction between row-type genes in barley controls meristem determinacy and reveals novel routes to improved grain.

大麦基因之间的相互作用控制分生组织的决定性，并揭示了改善谷物的新路线。

• DOI: 10.1111/nph.15548
• 发表时间: 2019-03
• 期刊: The New phytologist
• 作者: Zwirek M;Waugh R;McKim SM
• 通讯作者: McKim SM