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。核糖体是天然的纳米机器，负责将存储在细胞核中的信息转化为能够在细胞、组织或有机体内工作的蛋白质。核糖体的两个亚基(大的：60 S和小的：40 S)共同由81种蛋白质(核糖体蛋白：RP)组成，位于核糖体核糖核酸(RRNA)的支架上。我的研究计划专注于了解核糖体的生物发生--在植物中制造核糖体。对于每个RP，植物的基因组中有2到7个基因，从这些基因可以产生相同的RP，但在结构上有一定程度的变化(一种异构体)。要构建核糖体，需要大量的其他蛋白质、核糖体生物发生因子(RBF)以及其他因素。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(亚型)。异构体之间的这种差异水平表明，在任何一个植物细胞或组织中，核糖体群体可能是同质的--都具有相同的合成一系列蛋白质的能力，或者核糖体群体可能是异质性的，因此具有不同同工型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发挥作用的特定蛋白质来对变化的环境(细胞内部或外部)做出反应。通过拥有这样的核糖体保存库，植物能够经受住各种变化的环境条件。在我的研究计划中，我们选择了一些RP和RBF家族，在模式双子叶植物拟南芥中，以确定这些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家族每个都有两到三个亚型，而RBF家族由四个亚型组成。我们将对这些异构体以及携带每个异构体突变的植物进行分子和细胞生物学、生化和生理学研究，以确定它们在植物适应不断变化的环境条件中的作用(S)。*了解专门的核糖体的组装和功能将为我们提供手段，使我们能够设计出未来作物对未来气候变化条件的受控、优化的反应，并提供在体外构建能够高度专业化地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.