Biogenesis of the plant ribosome and its role in plant growth and development

核糖体是所有活细胞的基本组成部分——负责将储存在细胞核中的DNA信息转化为能够在细胞、组织或生物体中工作的蛋白质的天然纳米机器。核糖体的两个亚基（大：60 S和小：40 S）位于核糖体RNA （rRNA）支架上，由81个蛋白（核糖体蛋白：RPs）组成。我的研究项目集中在了解核糖体生物发生-核糖体的制造，在植物中。对于每个RP，植物的基因组中有2到7个基因，这些基因可以形成相同的RP，但在结构上有一定程度的差异（一种异构体）。为了构建一个核糖体，需要大量的其他蛋白质、核糖体生物生成因子（RBFs）以及其他因子。在植物中，对于每个RBF，又有一个基因家族产生每个因子略有不同的变异（同种异构体）。同种异构体之间的这种水平差异表明，在任何一个植物细胞或组织内，核糖体群体可能是同质的——所有的核糖体都具有相同的能力来合成一系列“保家卫国”的蛋白质，或者核糖体群体可能是异质的，具有不同同种异构体组成的核糖体使植物能够通过选择性地合成能够在变化的环境中起作用的特殊蛋白质来应对不断变化的环境（细胞内部或外部）。有了这样的核糖体储备，植物就能够承受大量不断变化的环境条件。在我的研究计划中，我们将重点研究模式植物拟南芥中的RP和RBF家族，以确定家族异构体在植物核糖体生物发生和功能中的作用。我们最初关注的五个RP家族每个都有两个或三个异构体，RBF家族由四个异构体组成。我们将开展分子和细胞生物学，生物化学和生理研究的异构体，以及植物携带突变的每一个异构体，以确定他们的作用(s)在植物适应不断变化的环境条件。***了解特化核糖体的组装和功能将为我们提供设计控制的手段，优化未来作物对未来气候变化条件的反应，并提供在体外构建能够高度特化合成特定蛋白质或蛋白质家族的核糖体的机会。

Ribosomes are fundamental constituents of all living cells - natural nano-machines responsible for the conversion of the information stored as DNA in the nucleus, into proteins capable of doing work within a cell, tissue or organism.The two subunits (large: 60 S and small: 40 S) of a ribosome are together comprised of 81 proteins (ribosomal proteins: RPs) located on a scaffold of ribosomal RNA (rRNA). My research program is focused on understanding ribosome biogenesis - the making of a ribosome, in plants. For each RP, plants have in their genomes between 2 and 7 genes from which the same RP, with some degree of variation in structure (an isoform), can be made. To build a ribosome, a large number of other proteins, ribosome biogenesis factors (RBFs), as well as other factors, are required. In plants, for each RBF there is again a family of genes that produce slightly different variations (isoforms) of each factor. This level of variation between isoforms suggests that within any one plant cell or tissue, the ribosome population may be homogeneous - all with the same ability to synthesis a 'house-keeping' array of proteins, or the ribosome population may be heterogeneous whereby ribosomes with different isoform compositions enable a plant to respond to changing environments (internal or external to the cell) by selectively synthesizing specialized proteins that can function within the changed environment. By having such a repertoire of ribosomes available to it, a plant is enabled to withstand a multitude of changing environmental conditions. In my research program, we are focusing on a select number of RP and RBF families, in the model dicot plant Arabidopsis, to identify the role of the family isoforms in plant ribosome biogenesis and function. The five RP families that we are initially focusing on each have two or three isoforms and the RBF family is comprised of four isoforms. We will be carrying out molecular and cellular biological, biochemical and physiological studies on the isoforms, as well as on plants carrying mutations for each isoform, to identify their role(s) in plant adaptability to changing environmental conditions.***Understanding the assembly and function of specialized ribosomes will provide us the means to engineer controlled, optimized responses of future crop plants to future climate change conditions and offer the opportunity to build ribosomes in vitro that are capable of the highly specialized synthesis of specific proteins or families of proteins.