Expression of taste signal transduction molecules in the caecum of common marmosets

The extraoral presence of taste signal transduction proteins has recently been reported in rodents and humans. Here, we report for the first time the presence of these signal transduction proteins in the caecum of a non-human primate, the common marmoset. Quantitative RT-PCR data on the gene expression of taste signal transduction molecules (gustducin and TRPM5) in common marmosets suggested high expression in the caecum, which was not observed in other non-human primates. Immunohistochemical analysis confirmed the specific presence of gustducin and taste receptors in marmoset caecal cells. These results may relate to the specific feeding behaviour of marmosets, which consume plant exudates, primarily gums.近期已有研究报道，啮齿类与人类体内存在口腔外分布的味觉信号转导蛋白。本研究首次在非人灵长类动物普通狨猴的盲肠中检测到此类信号转导蛋白的存在。针对普通狨猴体内味觉信号转导分子味导素（gustducin）与TRPM5的基因表达检测所获定量逆转录PCR（Quantitative RT-PCR）数据显示，其盲肠中存在高表达特征，而该现象在其他非人灵长类动物中尚未被观测到。免疫组织化学分析（Immunohistochemical analysis）进一步证实，普通狨猴盲肠细胞中特异性表达味导素与味觉受体。上述研究结果或与普通狨猴的特殊进食行为相关，该物种主要取食植物渗出液，尤以树胶为主。