Structure of NPP1, an Ectonucleotide Pyrophosphatase/Phosphodiesterase Involved in Tissue Calcification
摘要:
Ectonucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) converts extracellular nucleotides into inorganic pyrophosphate, whereas its close relative NPP2/autotaxin hydrolyzes lysophospholipids. NPP1 regulates calcification in mineralization-competent tissues, and a lack of NPP1 function underlies calcification disorders. Here, we show that NPP1 forms homodimers via intramembrane disulfide bonding, but is also processed intracellularly to a secreted monomer. The structure of secreted NPP1 reveals a characteristic bimetallic active site and a nucleotide-binding groove, but it lacks the lipid-binding pocket and open tunnel present in NPP2. A loop adjacent to the nucleotide-binding site, which is disordered in NPP2, is well ordered in NPP1 and might promote nucleotide binding. Remarkably, the N-terminal somatomedin B-like domains of NPP1, unlike those in NPP2, are flexible and do not contact the catalytic domain. Our results provide a structural basis for the nucleotide pyrophosphatase activity of NPP1 and help to understand how disease-causing mutations may affect NPP1 structure and function.
Bis(m-nitrophenyl) and bis(p-nitrophenyl) esters and the phosphorodiamidate of thymidine 5'-phosphate as potential sources of intracellular thymidine 5'-phosphate in mouse cells in culture
摘要:
Thymidine 5'-phosphate (TMP) derivatives with masked phosphate groups were synthesized in tritiated form from [methyl-3H]thymidine. They were of interest as models for 5' nucleotide derivatives that might be able to permeate mammalian cells and then liberate intracellular antimetabolite 5' nucleotides by loss of the masking groups. Mouse L fibroblasts were grown in vitro in the presence of 1 mM 5'-amino-5'-deoxythymidine, which was found to suppress greater than 99% of cellular thymidine kinase activity while inhibiting the rate of cell division by only 30%. The TMP derivatives were less effective than thymidine in labeling the deoxyribonucleic acid (DNA) of the L cells. The labeling was inhibited 95-99% by 5'-amino-5'-deoxythymidine, indicating that it represented incorporation into DNA of [3H]thymidine formed from degradation of the test compounds. No evidence was obtained that the compounds acted as sources of intracellular TMP by cell permeation followed by loss of phosphate blocking groups. Similar studies yielded no evidence that the bis(m-nitrophenyl) ester of TMP produced intracellular TMP by that route in the LM(TK-) strain of L cells that are genetically deficient in thymidine kinase.
Evidence for Direct Attack by Hydroxide in Phosphodiester Hydrolysis
作者:Adam G. Cassano、Vernon E. Anderson、Michael E. Harris
DOI:10.1021/ja020823j
日期:2002.9.1
deuterium isotopeeffects (D2Ok), ionic strength effects, and 18O isotopeeffects on the solvent nucleophile (18knuc). The D2Ok for hydroxide-catalyzed phosphodiester hydrolysis is slightly inverse (0.9 +/- 0.1), suggesting that a proton transfer does not occur in the transition state. A significant alpha effect is observed with hydroperoxide, demonstrating that oxyanions can act as nucleophiles in the reaction
[EN] NUCLEOSIDE 5'-PHOSPHOROTHIOATE ANALOGUES AND USES THEREOF<br/>[FR] ANALOGUES DE NUCLÉOSIDE 5'-PHOSPHOROTHIOATE ET LEURS UTILISATIONS
申请人:UNIV BAR ILAN
公开号:WO2013132489A1
公开(公告)日:2013-09-12
The invention provides particular mono- and dinucleoside 5'-phosphorothioate analogues, more particularly mono- or di- adenosine or uridine 5'-di- or tri- phosphorothioate analogues in which at least one of the bridging oxygen atoms of the phosphorothioate is replaced by a group such as -CH2-, and at least one of the non- bridging atoms or negatively-charged atoms of the phosphorothioate is either a sulfur atom or a sulfur ion; and pharmaceutical compositions thereof. These compounds are useful for treatment of neurodegenerative diseases or disorders such as Alzheimer's disease.
[EN] HIGHLY SELECTIVE AND POTENT NPP1 INHIBITORS BASED ON URIDINE-5'-P,-DITHIOPHOSPHATE ANALOGUES<br/>[FR] INHIBITEURS DE NPP1 HAUTEMENT SÉLECTIFS ET PUISSANTS À BASE D'ANALOGUES D'URIDINE-5'-P,-DITHIOPHOSPHATE
申请人:UNIV BAR ILAN
公开号:WO2020212995A1
公开(公告)日:2020-10-22
The invention relates to a novel highly selective and potent NPP1 inhibitors, compositions comprising such, and their use as pharmaceuticals.
该发明涉及一种新型高度选择性和强效的NPP1抑制剂,包括这种抑制剂的组合物以及它们作为药物的使用。
RAZZELL; KHORANA, Journal of Biological Chemistry, 1959, vol. 234, # 8, p. 2105 - 2113
作者:RAZZELL、KHORANA
DOI:——
日期:——
Moffatt, Biochemical Preparations, 1961, vol. 8, p. 100