The Saccharomyces cerevisiae mutation elm4-1 facilitates pseudohyphal differentiation and interacts with a deficiency in phosphoribosylpyrophosphate synthase activity to cause constitutive pseudohyphal growth.
The Saccharomyces cerevisiae mutation elm4-1 facilitates pseudohyphal differentiation and interacts with a deficiency in phosphoribosylpyrophosphate synthase activity to cause constitutive pseudohyphal growth.
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酿酒酵母突变elm4-1促进假菌丝分化，并与磷酸核糖焦磷酸合酶活性缺陷相互作用，导致组成型假菌丝生长。
DOI：
10.1128/mcb.14.7.4671-4681.1994
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发表时间：
1994
影响因子：
5.3
通讯作者：
Myers,AM
中科院分区：
文献类型：
--
作者：
Blacketer,MJ;Madaule,P;Myers,AM
在基于细长细胞形状的视觉筛选中选择酿酒酵母突变体E124。遗传分析表明，E124 包含两个独立的突变，pps1-1 和delm4-1，每个突变都会导致作为单基因性状遗传的不同表型。在丰富的培养基中，pps1-1 本身会导致倍增时间增加，但不会影响细胞形状，而 elm4-1 会导致适度的细胞伸长表型，但不会影响生长速率。重建的delm4-1 pps1-1双突变体在丰富的培养基中表现出合成表型，包括极端的细胞伸长和延迟的细胞分离，这都是假菌丝分化的特征。 Theelm4-1 突变被证明是一个主导因子，可增强假菌丝分化，以应对假菌丝正常生长的遗传背景中的普遍氮饥饿。因此，elm4-1 允许识别或响应由氮限制引起的假菌丝分化信号。PPS1 被分离出来，并被证明是一个先前未描述的基因，编码氨基酸序列与磷酸核糖焦磷酸合酶相似的蛋白质，磷酸核糖焦磷酸合酶是核苷酸、组氨酸和色氨酸生物合成中的限速酶。因此，ppsl-1突变可能产生氮限制信号，当与elm4-1结合时，即使在丰富的培养基中也会导致假菌丝生长。
Saccharomyces cerevisiaemutant E124 was selected in a visual screen based on elongated cell shape. Genetic analysis showed that E124 contains two separate mutations,pps1-1andelm4-1, each causing a distinct phenotype inherited as a single-gene trait. In rich medium,pps1-1by itself causes increased doubling time but does not affect cell shape, whereaselm4-1results in a moderate cell elongation phenotype but does not affect growth rate. Reconstructedelm4-1 pps1-1double mutants display a synthetic phenotype in rich medium including extreme cell elongation and delayed cell separation, both characteristics of pseudohyphal differentiation. Theelm4-1mutation was shown to act as a dominant factor that potentiates pseudohyphal differentiation in response to general nitrogen starvation in a genetic background in which pseudohyphal growth normally does not occur. Thus,elm4-1allows recognition of, or response to, a pseudohyphal differentiation signal that results from nitrogen limitation.PPS1was isolated and shown to be a previously undescribed gene coding for a protein similar in amino acid sequence to phosphoribosylpyrophosphate synthase, a rate-limiting enzyme in the biosynthesis of nucleotides, histidine, and tryptophan. Thus, theppsl-1mutation may generate a nitrogen limitation signal, which when coupled withelm4-1results in pseudohyphal growth even in rich medium.