Dual compartmental localization and function of mammalian NADP+-specific isocitrate dehydrogenase in yeast
Dual compartmental localization and function of mammalian NADP+-specific isocitrate dehydrogenase in yeast
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DOI：
10.1016/j.abb.2008.01.025
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发表时间：
2008-04-01
影响因子：
3.9
通讯作者：
McAlister-Henn, Lee
中科院分区：
文献类型：
--
作者：
Lu, Qian;Minard, Karyl I.;McAlister-Henn, Lee
NADP（+）特异性异柠檬酸脱氢酶（IDP）的同工酶在真核细胞的胞质、线粒体和过氧化物酶体区室中提供NADPH。纯化的IDP同工酶从酵母和小鼠的分析表明，一般对应的pH值最佳催化和pI值与pH值报告的居民细胞室。然而，小鼠IDP 2，在哺乳动物细胞中的胞质和过氧化物酶体室之间的分区，表现出广泛的pH值的最佳值和中间的pI值。小鼠IDP2被发现类似地共定位在两个细胞室中表达时，在酵母中的水平相当于那些内源性酵母同工酶。小鼠酶可以补偿酵母胞质IDP2和过氧化物酶体IDP3的损失。去除小鼠酶的过氧化物酶体靶向信号排除了过氧化物酶体中的定位和酵母IDP 3损失的补偿。(c)2008年爱思唯尔公司All rights reserved.
Isozymes of NADP(+)-specific isocitrate dehydrogenase (IDP) provide NADPH in cytosolic, mitochondrial, and peroxisomal compartments of eukaryotic cells. Analyses of purified IDP isozymes from yeast and from mouse suggest a general correspondence of pH optima for catalysis and pI values with pH values reported for resident cellular compartments. However, mouse IDP2, which partitions between cytosolic and peroxisomal compartments in mammalian cells, exhibits a broad pH optimum and an intermediate pI value. Mouse IDP2 was found to similarly colocalize in both cellular compartments when expressed in yeast at levels equivalent to those of endogenous yeast isozymes. The mouse enzyme can compensate for loss of yeast cytosolic IDP2 and of peroxisomal IDP3. Removal of the peroxisomal targeting signal of the mouse enzyme precludes both localization in peroxisomes and compensation for loss of yeast IDP3. (c) 2008 Elsevier Inc. All rights reserved.