MAP kinases have different functions in Dictyostelium G protein-mediated signaling.
MAP kinases have different functions in Dictyostelium G protein-mediated signaling.
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MAP 激酶在盘基网柄菌 G 蛋白介导的信号传导中具有不同的功能。
DOI：
10.1016/j.cellsig.2010.01.008
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发表时间：
2010
影响因子：
4.8
通讯作者：
Hadwiger,JeffreyA
中科院分区：
文献类型：
--
作者：
Nguyen,Hoai-Nghia;Raisley,Brent;Hadwiger,JeffreyA
细胞外信号调节激酶（ERK）是一类在真核细胞中的许多信号传导途径中起作用的MAP激酶，并且在某些情况下，单一刺激可以激活多于一种ERK，表明功能冗余或与共同途径的分歧。Dictyosteopathy discoideum只编码两种MAP激酶，ERK 1和ERK 2，这两种激酶都在发育生命周期中发挥作用。为了确定ERK 1和ERK 2是否具有重叠的功能，我们评估了ERK 1 −和ERK 2 −突变体在G蛋白介导的信号转导通路方面的趋化性和发育表型。ERK 1是Gα5介导的尖端形态发生和叶酸趋化性抑制所必需的，但不是cAMP刺激的趋化性或cGMP积累所必需的。ERK 2是响应于叶酸或cAMP刺激而磷酸化的主要MAPK。在erk 1-、erk 2-或erk 1-erk 2-突变体中细胞生长没有改变，但每种突变体在嵌合聚集体中显示出不同的细胞分选模式。在cAMP或叶酸刺激的细胞中，GFP-ERK 1或GFP-ERK 2融合蛋白在细胞质和细胞核中的分布没有明显改变。这些结果表明ERK 1和ERK 2在生长发育过程中G蛋白介导的信号传导中具有不同的作用。
Extracellular signal regulated kinases (ERKs) are a class of MAP kinases that function in many signaling pathways in eukaryotic cells and in some cases, a single stimulus can activate more than one ERK suggesting functional redundancy or divergence from a common pathway. Dictyostelium discoideum encodes only two MAP kinases, ERK1 and ERK2, that both function during the developmental life cycle. To determine if ERK1 and ERK2 have overlapping functions, chemotactic and developmental phenotypes of erk1−and erk2−mutants were assessed with respect to G protein-mediated signal transduction pathways. ERK1 was specifically required for Gα5-mediated tip morphogenesis and inhibition of folate chemotaxis but not for cAMP-stimulated chemotaxis or cGMP accumulation. ERK2 was the primary MAPK phosphorylated in response to folate or cAMP stimulation. Cell growth was not altered in erk1−, erk2−or erk1−erk2−mutants but each mutant displayed a different pattern of cell sorting in chimeric aggregates. The distribution of GFP-ERK1 or GFP-ERK2 fusion proteins in the cytoplasm and nucleus was not grossly altered in cells stimulated with cAMP or folate. These results suggest ERK1 and ERK2 have different roles in G protein-mediated signaling during growth and development.