Functional analysis of the C-terminal cytoplasmic region of the M-factor receptor in fission yeast
Functional analysis of the C-terminal cytoplasmic region of the M-factor receptor in fission yeast
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DOI：
10.1046/j.1365-2443.2001.00415.x
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发表时间：
2001-03-01
期刊：
影响因子：
2.1
通讯作者：
Yamamoto, M
中科院分区：
文献类型：
--
作者：
Hirota, K;Tanaka, K;Yamamoto, M
背景：酵母交配信息素受体有助于G蛋白偶联信号转导的研究。到目前为止，对芽殖酵母α因子受体的分子解剖已经进行了广泛的研究，但对另一个遗传易感酵母物种分裂酵母的信息素受体的分析还很少。结果：我们分析了分裂酵母的M因子受体Map3p，C端54个氨基酸的截短使Map3p对野生型显性-负性。这种形式被称为Map3-dn9p，它能够诱导信息素依赖的基因表达，尽管它不能指导适当的接合，但Map3-dn9p既不能引发接合管的定向投射，也不能诱导对与受体内吞相关的信息素信号的适应。缺失和替换分析表明，C-末端区域的完整性，而不是其中特定的氨基酸残基亚群，对各自的Map3p活性至关重要。结论：Map3p的C末端区域对于信息素信号本身来说是必不可少的，但对于适应和信息素诱导的接合管的形成是关键的，芽期酵母α因子受体也是如此。然而，在泛素化的必要性方面，分裂酵母和芽生酵母诱导适应的机制似乎不同。
Background: Yeast mating-pheromone receptors facilitate the study of G protein-coupled signal transduction. To date, molecular dissection of the budding yeast alpha -factor receptor has been done extensively, but little analysis has been performed with pheromone receptors of fission yeast, another genetically tractable yeast species.Results: We analysed the fission yeast M-factor receptor Map3p, Truncation of the C-terminal 54 amino acids made Map3p dominant-negative over the wild-type. This form, called Map3-dn9p, was competent in the induction of pheromone-dependent gene expression, although it could not direct proper conjugation, Map3-dn9p failed both to provoke the orientated projection of conjugation tubes and to induce adaptation to the pheromone signal associated with endocytosis of the receptor. Deletion and substitution analyses suggested that the integrity of the C-terminal region, rather than a specific subgroup of amino acid residues therein, was vital for the respective Map3p activities. Ubiquitination of the C-terminus was not absolutely essential for Map3p function.Conclusions: The C-terminal region of Map3p is dispensable for the pheromone signalling per se, but is pivotal for adaptation and pheromone-induced conjugation tube formation, as is true with the budding yeast alpha -factor receptor. However, the mechanisms which induce adaptation appear to differ between fission and budding yeast concerning the necessity of ubiquitination.