Mutations in the Saccharomyces cerevisiae opi3 gene: effects on phospholipid methylation, growth and cross-pathway regulation of inositol synthesis.
Mutations in the Saccharomyces cerevisiae opi3 gene: effects on phospholipid methylation, growth and cross-pathway regulation of inositol synthesis.
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酿酒酵母 opi3 基因突变：对磷脂甲基化、生长和肌醇合成跨途径调节的影响。
DOI：
10.1093/genetics/122.2.317
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发表时间：
1989
期刊：
影响因子：
3.3
通讯作者：
Henry,SA
中科院分区：
文献类型：
--
作者：
McGraw,P;Henry,SA
我们报告了两个新的突变体的分离，EMS诱变，并在体外构建一个插入等位基因，使用克隆的基因。我们已经证明，opi 3突变导致的缺陷，在两个终端磷脂N-甲基转移酶（PLMT）的活动所需的从头合成PC（磷脂酰胆碱）。opi 3突变体，在某些生长条件下，产生膜几乎没有PC，但令人惊讶的是，没有突变体显示出严格的营养缺陷型胆碱的要求。尽管opi 3突变体在没有补充剂的情况下生长，但我们已经表明，非典型膜影响突变株启动对数期生长和维持稳定期活力的能力。对数期生长的开始通过添加胆碱或在较小程度上DME（二甲基乙醇胺）而增强，并且通过添加MME（单甲基乙醇胺）而延迟。突变体细胞在没有DME或胆碱的情况下在细胞周期的稳定期失去活力，并且对于37度的生长也是温度敏感的，特别是在含有MME的培养基中。这些生长缺陷与膜中存在特定磷脂有关。opi 3生长缺陷受到磷脂甲基化途径中的一种不寻常突变的抑制，该突变在opi 3病变影响的反应之前立即干扰N-甲基转移酶（PEMT）活性。我们认为这种突变cho 2-S改变了PEMT的底物特异性。opi 3突变的次要作用是破坏PI（磷脂酰肌醇）前体肌醇合成的交叉途径调节。肌醇的合成通过编码肌醇-1-磷酸合酶的INO 1基因的调节来控制。这种高度调节的基因在opi 3突变体中组成型表达。我们已经使用opi 3菌株证明PC或PD（磷脂酰二甲基乙醇胺）的合成将恢复INO 1基因的正常调节。
We report the isolation of two new opi3 mutants by EMS mutagenesis, and construction of an insertion allele in vitro using the cloned gene. We have demonstrated that the opi3 mutations cause a deficiency in the two terminal phospholipid N-methyltransferase (PLMT) activities required for the de novo synthesis of PC (phosphatidylcholine). The opi3 mutants, under certain growth conditions, produce membrane virtually devoid of PC although, surprisingly, none of the mutants displays a strict auxotrophic requirement for choline. Although the opi3 mutants grow without supplements, we have shown that the atypical membrane affects the ability of the mutant strains to initiate log phase growth and to sustain viability at stationary phase. The commencement of log phase growth is enhanced by addition of choline or to a lesser extent DME (dimethylethanolamine), and retarded by addition of MME (monomethylethanolamine). The mutant cells lose viability at the stationary phase of the cell cycle in the absence of DME or choline, and are also temperature sensitive for growth at 37 degrees especially in media containing MME. These growth defects have been correlated to the presence of specific phospholipids in the membrane. The opi3 growth defects are suppressed by an unusual mutation in the phospholipid methylation pathway that perturbs the N-methyltransferase (PEMT) activity immediately preceding the reactions affected by the opi3 lesion. We believe this mutation, cho2-S, alters the substrate specificity of the PEMT. A secondary effect of opi3 mutations is disruption of the cross pathway regulation of the synthesis of the PI (phosphatidylinositol) precursor inositol. Synthesis of inositol is controlled through regulation of the INO1 gene which encodes inositol-1-phosphate synthase. This highly regulated gene is expressed constitutively in opi3 mutants. We have used the opi3 strains to demonstrate that synthesis of either PC or PD (phosphatidyldimethylethanolamine) will restore normal regulation of the INO1 gene.
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酵母磷脂酰乙醇胺甲基化途径。
影响因子：
4.8
作者：
Tsutomu Kodaki;S. Yamashita
通讯作者：
S. Yamashita
影响因子：
4.8
作者：
F. Audubert;D. Vance
通讯作者：
D. Vance
DOI：
10.1016/s0021-9258(19)69102-7
发表时间：
1981-07
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
T. Donahue;S. Henry
通讯作者：
T. Donahue;S. Henry
粗糙脉孢菌突变株中的磷脂变化。
DOI：
10.1016/s0021-9258(18)91248-2
发表时间：
1964
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
B. Crocken;J. F. Nyc
通讯作者：
J. F. Nyc
DOI：
10.1073/pnas.78.1.238
发表时间：
1981-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
FRIED, HM;WARNER, JR
通讯作者：
WARNER, JR