Functions of serine hydroxymethyltransferases in plant metabolism and gene regulation

丝氨酸羟甲基转移酶(SHM)是一种普遍存在的酶。在所有真核生物中，异构体存在于不同的细胞室中，它们参与丝氨酸的合成，并从丝氨酸的分解代谢中提供一碳单位。在植物的光合作用器官中，线粒体膜SHM1是光呼吸乙醇酸循环所必需的。植物SHM由基因家族编码，在拟南芥中有7个成员，在水稻中可能有5个成员。除了光呼吸SHM1外，对其他亚型的了解非常有限。这个项目使用拟南芥作为模型来回答关于植物中不同位置的SHM亚型的特定代谢功能的问题。这一新的知识将对理解植物的一碳代谢产生影响，包括相关的代谢途径和调控过程。

Serine hydroxymethyltransferase (SHM) is a ubiquitous enzyme. In all eukaryotes, isoforms occur in different cellular compartments where they contribute to serine synthesis and pro-vide one-carbon units from serine catabolism. In photosynthesizing organs of plants, mito-chondrial SHM1 is obligatory for the functioning of the photorespiratory glycolate cycle. Plant SHMs are encoded by gene families with seven members in Arabidopsis and probably five members in rice. Except of the photorespiratory SHM1, knowledge about the other isoforms is very limited. This project uses Arabidopsis as a model to answer questions concerning specific metabolic functions of differentially located SHM isoforms in plants. This new knowl-edge will have impact on the understanding of plant one-carbon metabolism including related metabolic pathways and regulatory processes.