Activation of Non-Photosynthetic Leaf Cells for Improved Productivity

激活非光合作用叶细胞以提高生产力

• 批准号: BB/P003117/1
• 负责人: Julian Hibberd
• 金额: $ 364.49万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FP003117%2F1
• 关键词: Activation; Non; Photosynthetic; Leaf; Cells

This proposal aims to answer a fundamental question in biology that will enable increased photosynthetic capacity to be engineered and therefore productivity to be improved in a wide range of plant species. Specifically, it is proposed to elucidate the genetic mechanisms that determine whether a cell in a leaf becomes photosynthetic or not and exploit these mechanisms to activate photosynthesis in inactive cells within the leaf. This utilization of conventionally inactive leaf cells for photosynthesis could lead to a step-change in agricultural productivity. The form of photosynthesis used by the majority of plants is referred to as C3 photosynthesis because the initial product of CO2 fixation contains three carbons. Whilst mesophyll cells of C3 species green up in response to light, other cells in the leaf such as the bundle sheath do not. This proposal aims to elucidate the genetic basis of this distinction. To understand factors regulating differential photosynthetic competence, rice will be used as a model system. Rice is the most appropriate system to use because it has a relatively small genome that is better annotated than any other cereal genome. These features make genome-wide analysis of gene expression profiles and other computational analyses straightforward. In addition, the rice leaf has a developmental trajectory that is perfectly suited to the biological question being addressed. Specifically, photosynthesis is activated along the rice leaf, with inactive cells at the base of the leaf and fully active cells at the tip. This gradient can be used to dissect the dynamics and mechanisms by which photosynthesis is activated. Moreover as photosynthetically active and inactive cells develop side-by-side in the same gradient it is an ideal system in which to compare the development of photosynthetic versus non-photosynthetic cell-types.The research programme will be split into six work packages (WP). WP1 will compute a Gene Regulatory Network for Photosynthesis (GRN-Ps). This will identify the likely regulatory components involved in the photosynthesis activation gradient. WP2 will use the GRN-Ps to identify novel regulators of photosynthetic development in the C3 mesophyll and elucidate the spatial and temporal interactions between these regulatory components. Functional analyses in rice will then test the extent to which these regulators can be modified and recruited to function in the bundle sheath. WP3 will test the hypothesis that photosynthesis is limited in the C3 bundle sheath because normal light-induced expression of photosynthesis genes is repressed in this cell type, and WP4 will discover the components of the repression mechanism. WP5 will then generate a toolkit of candidate cis and trans regulators of photosynthetic activation (or derepression) that will be tested in pairwise combinations in a rapid transient assay system. Finally, WP6 will build minimal synthetic circuits to activate and maintain photosynthesis in non-photosynthetic cells of rice leaves. Together the outputs of this research will provide design parameters for a synthetic approach to improving photosynthetic efficiency for the future.

该提案旨在回答生物学中的一个基本问题，该问题将使增加的光合能力能够被工程化，从而在广泛的植物物种中提高生产力。具体而言，它建议阐明的遗传机制，决定是否在一个细胞的叶片成为光合作用或没有，并利用这些机制，以激活光合作用在叶片内的非活性细胞。这种利用传统上不活跃的叶细胞进行光合作用的方法可能会导致农业生产力的逐步变化。大多数植物使用的光合作用形式被称为C3光合作用，因为CO2固定的初始产物含有三个碳。C3植物的叶肉细胞对光有绿色的反应，而叶中的其他细胞如维管束鞘则没有。这一建议旨在阐明这种区别的遗传基础。为了了解调节差异光合能力的因素，水稻将被用作模型系统。水稻是最适合使用的系统，因为它的基因组相对较小，比任何其他谷物基因组都更好地注释。这些特征使得基因表达谱的全基因组分析和其他计算分析变得简单。此外，水稻叶片的发育轨迹非常适合正在解决的生物学问题。具体地说，光合作用是沿着水稻叶片沿着被激活的，在叶片基部有不活跃的细胞，而在叶尖有完全活跃的细胞。这个梯度可以用来剖析光合作用被激活的动力学和机制。此外，由于光合活性细胞和非光合活性细胞在同一梯度中并排发育，因此这是比较光合细胞与非光合细胞类型发育的理想系统。WP 1将计算光合作用基因调控网络（GRN-Ps）。这将确定参与光合作用激活梯度的可能的调节组分。WP 2将使用GRN-Ps来识别C3叶肉中光合作用发育的新调节剂，并阐明这些调节组分之间的空间和时间相互作用。水稻的功能分析，然后将测试在何种程度上，这些监管机构可以修改和招募功能的维管束鞘。WP 3将测试光合作用在C3束鞘中受到限制的假设，因为正常的光诱导的光合作用基因表达在这种细胞类型中受到抑制，WP 4将发现抑制机制的组成部分。然后，WP 5将生成光合激活（或去阻遏）的候选顺式和反式调节剂的工具包，这些调节剂将在快速瞬时测定系统中成对组合进行测试。最后，WP 6将建立最小的合成电路，以激活和维持水稻叶片非光合细胞的光合作用。这项研究的结果将为未来提高光合效率的合成方法提供设计参数。

项目成果

Gene duplication accelerates the pace of protein gain and loss from plant organelles

基因复制加速了植物细胞器蛋白质获得和损失的速度

• DOI: 10.1101/415125
• 发表时间: 2018
• 作者: Costello R

Rubisco Adaptation Is More Limited by Phylogenetic Constraint Than by Catalytic Trade-off.

• DOI: 10.1093/molbev/msab079
• 发表时间: 2021-06-25
• 期刊: Molecular biology and evolution
• 影响因子: 10.7
• 作者: Bouvier JW;Emms DM;Rhodes T;Bolton JS;Brasnett A;Eddershaw A;Nielsen JR;Unitt A;Whitney SM;Kelly S
• 通讯作者: Kelly S

A single promoter-TALE system for tissue-specific and tuneable expression of multiple genes in rice.

• DOI: 10.1111/pbi.13864
• 发表时间: 2022-09
• 期刊: PLANT BIOTECHNOLOGY JOURNAL
• 影响因子: 13.8
• 作者: Danila, Florence;Schreiber, Tom;Ermakova, Maria;Hua, Lei;Vlad, Daniela;Lo, Shuen-Fang;Chen, Yi-Shih;Lambret-Frotte, Julia;Hermanns, Anna S.;Athmer, Benedikt;von Caemmerer, Susanne;Yu, Su-May;Hibberd, Julian M.;Tissier, Alain;Furbank, Robert T.;Kelly, Steven;Langdale, Jane A.
• 通讯作者: Langdale, Jane A.

Rubisco adaptation is more limited by phylogenetic constraint than by catalytic trade-off

Rubisco 适应更多地受到系统发育约束而不是催化权衡的限制

• DOI: 10.1101/2020.09.15.298075
• 发表时间: 2020
• 作者: Bouvier J