T1R1和T1R3在从江香猪附睾发育中的表达模式

为研究味觉受体第一家族亚型1（T1R1）和3（T1R3）在从江香猪附睾发育过程中的表达模式，探讨味觉受体在哺乳动物雄性生殖机能中可能发挥的作用及潜在医学价值，本试验以从江香猪附睾组织为研究对象，分析附睾发育4个关键时期：初情前（15 d）、初情时（30 d）、初情后（60 d）和性成熟期（180 d）T1R1与T1R3的差异表达。采用实时荧光定量PCR、免疫组织化学（IHC）和Western blot检测两个味觉受体在不同日龄从江香猪附睾组织中转录、翻译水平的变化及其分布情况。RT-qPCR结果表明：TAS1R1与TAS1R3 mRNA在从江香猪附睾初情前（15 d）至性成熟期（180 d）表达量逐渐增加，且任意两个时期间差异极显著（P<0.01）。Western blot结果显示，T1R1/T1R3蛋白在180 d表达量最高，在15 d表达量最低，两者之间差异显著（P<0.05），平均表达丰度依次为180 d > 30 d > 60 d > 15 d。IHC结果显示，T1R1和T1R3蛋白在各日龄组从江香猪附睾组织均有分布，其中T1R1蛋白主要在上皮细胞膜上，尤其是基细胞和窄细胞；而T1R3蛋白主要在微绒毛、环状空泡和精子呈强阳性表达。综上，本研究发现不同日龄从江香猪附睾的T1R1/T1R3表达从15 d逐渐增加，至性成熟达到峰值，这一表达变化与附睾上皮基细胞和窄细胞及微绒毛的T1R1/T1R3的差异表达有关，这些特殊的表达模式与附睾生理功能存在时间关联，故推测T1R1和T1R3参与附睾内精子成熟和储存的调节过程。

Expression Patterns of T1R1 and T1R3 in the Congjiang Xiang Pig during Epididymal Development

The aim of this experiment was to study the expression pattern of taste receptor family 1 subtypes 1 (T1R1) and 3 (T1R3) during epididymal development of Congjiang Xiang pig, and to explore the possible role of these taste receptors in mammalian male reproductive function and its potential medical value. In this study, the differential expressions of T1R1 and T1R3 in epididymis at 4 key developmental periods (neonatal (15 d), peri-puberty (30 d), puberty (60 d) and sexual maturity (180 d)) of Congjiang Xiang pigs were analyzed. RT-qPCR, immunohistochemistry (IHC) and Western blot were used to detect the changes and distribution of the two taste receptors in epididymis of Congjiang Xiang pigs at different ages. The results of RT-qPCR showed that the expression of TAS1R1 and TAS1R3 mRNA increased gradually from neonatal (15 d) to sexual maturity (180 d), and there was a significant difference between each period (P<0.01). The results of Western blot showed that the expression of T1R1/T1R3 protein was the highest on the 180 d and the lowest on the 15 d. The average protein abundance of T1R1/T1R3 was as follows: 180 d > 30 d > 60 d > 15 d. The results of IHC showed that T1R1 and T1R3 proteins were distributed in the epididymis of Congjiang Xiang pigs at 4 periods, in which T1R1 protein was mainly concentrated in epithelial cell membrane, especially in basal and narrow cells, while T1R3 protein was strongly positive in stereocilia, annular vacuoles and spermatozoa. In summary, the expression of T1R1/T1R3 in the epididymis of Congjiang Xiang pigs increased gradually from 15 d to the peak of sexual maturation, which was related to the differential expression of T1R1/T1R3 in epithelial basal cells, narrow cells and stereocilia of epididymis. These special expression patterns were time related to the physiological function of epididymis, so it is speculated that T1R1/T1R3 are involved in the regulation of sperm maturation and storage in epididymis.