Key amino acids alter activity and trafficking of a well-conserved olfactory receptor.
Key amino acids alter activity and trafficking of a well-conserved olfactory receptor.
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关键氨基酸改变保守的嗅觉受体的活性和运输。
DOI：
10.1152/ajpcell.00440.2021
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Pluznick,JenniferL
中科院分区：
文献类型：
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作者：
Xu,Jiaojiao;Pluznick,JenniferL
在这项研究中，我们阐明了调节一个高度保守的嗅觉受体（OR），嗅觉受体558 （Olfr558）及其人类同源嗅觉受体51E1 （OR51E1）的运输和活性的因素。结果表明，丁酸盐激活Olfr558/OR51E1导致cAMP的产生，并引起Ca2+内流。我们还发现嗅G蛋白（Golf）增加了Olfr558/OR51E1激活诱导的cAMP产生，但不影响运输。考虑到OR51E1和Olfr558之间93%的序列同源性，令人惊讶的是，OR51E1的表面表达明显更多，但总蛋白表达相似。我们发现用OR51E1的n端替换Olfr558的n端显著增加了转运；相比之下，OR51E1的TM2、TM3或TM4结构域没有引起表面表达的变化。先前对人类OR51E1单核苷酸多态性（snp）的分析发现，主要在南亚发现的A156T突变体是最丰富的（尽管仍然罕见）。我们发现OR51E1 A156T突变体减少了表面表达和cAMP的产生，但总蛋白表达没有变化。总之，这项研究发现了在蛋白质运输中起关键作用的蛋白质区域和特定氨基酸残基，并阐明了Golf对人类和小鼠OR调节的共同作用。
In this study, we elucidate factors that regulate the trafficking and activity of a well-conserved olfactory receptor (OR), olfactory receptor 558 (Olfr558), and its human ortholog olfactory receptor 51E1 (OR51E1). Results indicate that butyrate activates Olfr558/OR51E1 leading to the production of cAMP, and evokes Ca2+influx. We also find olfactory G protein (Golf) increases cAMP production induced by Olfr558/OR51E1 activation but does not affect trafficking. Given the 93% sequence identity between OR51E1 and Olfr558, it is surprising to note that OR51E1 has significantly more surface expression yet similar total protein expression. We find that replacing the Olfr558 N-terminus with that of OR51E1 significantly increases trafficking; in contrast, there is no change in surface expression conferred by the OR51E1 TM2, TM3, or TM4 domains. A previous analysis of human OR51E1 single nucleotide polymorphisms (SNPs) identified an A156T mutant primarily found in South Asia as the most abundant (albeit still rare). We find that the OR51E1 A156T mutant has reduced surface expression and cAMP production without a change in total protein expression. In sum, this study of a well-conserved olfactory receptor identifies both protein regions and specific amino acid residues that play key roles in protein trafficking and also elucidates common effects of Golf on the regulation of both the human and murine OR.