Regulation of Dictyostelium early development genes in signal transduction mutants.
Regulation of Dictyostelium early development genes in signal transduction mutants.
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信号转导突变体中盘基网柄菌早期发育基因的调控。
DOI：
10.1006/dbio.1995.1267
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Podgorski,GJ
中科院分区：
文献类型：
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作者：
Wu,L;Hansen,D;Franke,J;Kessin,RH;Podgorski,GJ
分泌的环核苷酸磷酸二酯酶（PDE）及其糖蛋白抑制剂（PDI）是在变形网骨藻开始发育时首先表达的基因之一。我们使用了一系列信号转导缺陷的突变体来研究cAMP受体1和3、Gα2、Gβ、腺苷酸环化酶（ACA）或蛋白激酶A催化亚基（PKAcat）是否是PDE和PDI转录本最初出现或随后调节所必需的。PDE基因在营养生长期间产生1.9-kb的转录物，然后在发育的早期产生2.4-kb的转录物。CAR 1、Gα2、Gβ和ACA突变体中2.4 kb转录物的调控与同基因亲本菌株相似，尽管其水平在携带CAR 1突变的菌株中降低。CAR 1/CAR 3双突变体也产生较少的PDE转录物，但PDE基因仍然可被cAMP诱导。PKAcat突变体产生2.4 kb PDE转录本，但在该突变体中，营养转录本在发育中保留。CAR 1和CAR 3不是PDI基因转录所需的，但缺失CAR 1导致PDI转录物的过量产生。PDI基因的诱导或阻遏不需要Gα2、Gβ或ACA。合成PDI转录物需要PKAcat。结果表明，这些早期基因通过Gα2/Gβ非依赖性机制和绝对依赖于PKAcat的PDI的两个阶段的调节。
The secreted cyclic nucleotide phosphodiesterase (PDE) and its glycoprotein inhibitor (PDI) are among the first genes expressed when Dictyostelium amoebae begin their development. We used a series of mutants with defects in signal transduction to ask whether cAMP receptors 1 and 3, Gα2, Gβ, adenylyl cyclase (ACA), or the protein kinase A catalytic subunit (PKAcat) are required for the initial appearance or later regulation of the PDE and the PDI transcripts. The PDE gene produces a 1.9-kb transcript during vegetative growth and then a 2.4-kb transcript during the early hours of development. Regulation of the 2.4-kb transcript in CAR1, Gα2, Gβ, and ACA mutants is similar to that of isogenic parental strains, although its level is reduced in strains that carry the CAR1 mutation. CAR1/CAR3 double mutants also produce less PDE transcript, but the PDE gene remains inducible by cAMP. The PKAcat mutant produces the 2.4-kb PDE transcript, but in this mutant the vegetative transcript is retained in development. CAR1 and CAR3 are not required for transcription of the PDI gene, but deleting CAR1 leads to overproduction of the PDI transcript. Induction or repression of the PDI gene does not require Gα2, Gβ, or ACA. PKAcat is required for synthesis of the PDI transcript. The results suggest a two-stage regulation of these early genes through a Gα2/Gβ-independent mechanism and an absolute dependence of PDI on the PKAcat.