期刊
NATURE COMMUNICATIONS
卷 12, 期 1, 页码 -出版社
NATURE PORTFOLIO
DOI: 10.1038/s41467-021-27152-4
关键词
-
资金
- Deutsche Forschungsgemeinschaft (DFG) [WI3411/8-1, INST 187/741-1 FUGG, GRK1798]
- National Research Foundation of Korea (NRF) by the Korea government (MSIT) [2020R1A4A1018890]
- National Research Foundation of Korea [2020R1A4A1018890] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
The study focuses on the dephosphorylation of XMP in plant cells and identifies an XMP phosphatase in Arabidopsis with specificity to XMP. The researchers demonstrate that XMPP initiates the catabolism of adenylate-derived nucleotides in vivo, while guanylates enter catabolism through a different pathway. The crystal structure and mutational analysis of XMPP provide insights into its high substrate specificity and efficient catalysis of the small XMP pool in vivo.
Dephosphorylation of xanthosine monophosphate (XMP) initiates purine nucleotide catabolism in plant cells. Here the authors identify an XMP phosphatase from Arabidopsis that channels XMP towards catabolism in vivo and demonstrate the structural basis for its XMP specificity. In plants, guanosine monophosphate (GMP) is synthesized from adenosine monophosphate via inosine monophosphate and xanthosine monophosphate (XMP) in the cytosol. It has been shown recently that the catabolic route for adenylate-derived nucleotides bifurcates at XMP from this biosynthetic route. Dephosphorylation of XMP and GMP by as yet unknown phosphatases can initiate cytosolic purine nucleotide catabolism. Here we show that Arabidopsis thaliana possesses a highly XMP-specific phosphatase (XMPP) which is conserved in vascular plants. We demonstrate that XMPP catalyzes the irreversible entry reaction of adenylate-derived nucleotides into purine nucleotide catabolism in vivo, whereas the guanylates enter catabolism via an unidentified GMP phosphatase and guanosine deaminase which are important to maintain purine nucleotide homeostasis. We also present a crystal structure and mutational analysis of XMPP providing a rationale for its exceptionally high substrate specificity, which is likely required for the efficient catalysis of the very small XMP pool in vivo.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据