New insights into the mechanism of light modulated signaling by heterotrimeric G-proteins: ENVOY acts on gna1 and gna3 and adjusts cAMP levels in Trichoderma reesei (Hypocrea jecorina).
New insights into the mechanism of light modulated signaling by heterotrimeric G-proteins: ENVOY acts on gna1 and gna3 and adjusts cAMP levels in Trichoderma reesei (Hypocrea jecorina).
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DOI：
10.1016/j.fgb.2010.12.009
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发表时间：
2011-06
影响因子：
3
通讯作者：
Schmoll, Monika
中科院分区：
文献类型：
--
作者：
Tisch, Doris;Kubicek, Christian P.;Schmoll, Monika
关键词：
环境信号的感知通常是由G蛋白偶联受体及其同源异源三聚体G蛋白介导的。在里氏木霉(Hypocrea Jecorina)中，通过G蛋白α亚基GNA1和GNA3传递的信号会引起纤维素酶转录水平的相当大的调节，这种调节的程度取决于光状态。因此，我们打算阐明光反应和异源三聚体G蛋白信号之间的潜在机制。对双突变菌株的分析表明，在没有PAS/LOV结构域蛋白特使(ENV1)的情况下，GNA1或GNA3的结构性激活导致在黑暗中结构性G-α激活的表型。在光照下，Δenv1在生长、分生孢子形成和纤维素酶基因转录方面表现为缺失表型。此外，env1的缺失会导致细胞内cAMP积聚减少，即使是在GNA1或GNA3的结构性激活时也是如此。在光照条件下，添加cAMP使所有缺乏env1的菌株的生长表型更加严重，而添加磷酸二酯酶抑制剂咖啡因则挽救了这些菌株的生长表型。因此，ENV1被认为通过调节GNA1和GNA3的转录水平以及对cAMP水平的作用--可能是通过抑制磷酸二酯酶--来将光反应途径与通过异源三聚体G蛋白级联的营养信号联系起来。
Sensing of environmental signals is often mediated by G-protein coupled receptors and their cognate heterotrimeric G-proteins. In Trichoderma reesei (Hypocrea jecorina) the signals transmitted via the G-protein alpha subunits GNA1 and GNA3 cause considerable modulation of cellulase transcript levels and the extent of this adjustment is dependent on the light status. We therefore intended to elucidate the underlying mechanism connecting light response and heterotrimeric G-protein signaling. Analysis of double mutant strains showed that constitutive activation of GNA1 or GNA3 in the absence of the PAS/LOV domain protein ENVOY (ENV1) leads to the phenotype of constitutive G-alpha activation in darkness. In light, however the deletion-phenotype of Δenv1 was observed with respect to growth, conidiation and cellulase gene transcription. Additionally deletion of env1 causes decreased intracellular cAMP accumulation, even upon constitutive activation of GNA1 or GNA3. While supplementation of cAMP caused an even more severe growth phenotype of all strains lacking env1 in light, addition of the phosphodiesterase inhibitor caffeine rescued the growth phenotype of these strains. ENV1 is consequently suggested to connect the light response pathway with nutrient signaling by the heterotrimeric G-protein cascade by adjusting transcript levels of gna1 and gna3 and action on cAMP levels – presumably through inhibition of a phosphodiesterase.
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影响因子：
11.4
作者：
Chen, Chen-Hui;Ringelberg, Carol S.;Loros, Jennifer J.
通讯作者：
Loros, Jennifer J.
影响因子：
3
作者：
Castellanos, Francisco;Schmoll, Monika;Ulises Esquivel-Naranjo, Edgardo
通讯作者：
Ulises Esquivel-Naranjo, Edgardo
影响因子：
--
作者：
Hicks, JK;Bahn, YS;Heitman, J
通讯作者：
Heitman, J
DOI：
10.1073/pnas.93.24.14122
发表时间：
1996-11-26
影响因子：
11.1
作者：
Gao, SJ;Nuss, DL
通讯作者：
Nuss, DL
影响因子：
64.5
作者：
Heintzen, C;Loros, JJ;Dunlap, JC
通讯作者：
Dunlap, JC