BDNF in adult mouse taste cells

本研究的目的是利用BDNF LacZ转基因小鼠来确定BDNF在成年小鼠味觉细胞中的作用。第一个目标是确定成年小鼠中哪种味觉细胞表达BDNF。具体来说，BDNF是否存在于新分裂的味觉细胞、未成熟的味觉细胞或表型成熟的味觉细胞中。如果BDNF存在于成熟的味觉细胞中，我有兴趣确定BDNF存在于哪种免疫组织化学和形态学类型的味觉细胞中。我将使用双标记免疫组织化学来实现这一目的。为了确定细胞的出生日期，我将给小鼠注射5 '-溴-2'脱氧尿苷，它可以掺入分裂细胞的DNA中。我也有兴趣确定什么影响（S）味蕾神经支配的损失将对BDNF的表达和什么影响（S）随后的再生和味蕾的神经支配将对BDNF的表达。为了实现这一目标，我将手术粉碎BDNF-LacZ小鼠的味觉神经，并让小鼠在神经粉碎后连续存活更长的时间，以观察神经变性和再生对味蕾中BDNF表达的影响。我的最终目标是确定成年人味蕾中BDNF表达的缺失对味蕾、味觉神经纤维和味觉神经节细胞有什么影响。由于我有兴趣研究BDNF表达缺失对成年人味觉系统的影响，并且我不想破坏味蕾的初始发育，因此我将使用组织特异性条件敲除小鼠，并仅在成年小鼠的舌头中敲除BDNF表达。我也可以切断组织特异性条件性BDNF敲除小鼠味蕾的神经，看看神经纤维是否会再生并重新支配不再表达BDNF的味蕾。这一目标将确定BDNF在成年小鼠味觉细胞中的作用，而不影响味蕾的初始发育。

The goals of this study are to use BDNF-LacZ transgenic "knock-in" mice to determine the role of BDNF in adult mouse taste cells. The first aim will determine which taste cell types express BDNF in the adult mouse. Specifically, whether BDNF is present in newly divided taste cells, immature taste cells, or phenotypically mature taste cells. If BDNF is present in mature taste cells, I am interested in determining which immunohistochemical and morphological classes of taste cells BDNF is present in. I will use double-label immunohistochemistry to achieve this aim. To birthdate cells I will inject mice with 5'-Bromo-2' deoxyuridine which incorporates into the DNA of dividing cells. I am also interested in determining what effect(s) loss of taste bud innervation will have on the expression of BDNF and what effect(s) subsequent regeneration and innervation of taste buds will have on the expression of BDNF. To achieve this aim I will surgically crush the gustatory nerves in BDNF-LacZ mice and let the mice live for successively longer days post nerve crush to look at the effect(s) nerve degeneration and regeneration has on BDNF expression in taste buds. For my final aim, 1 am interested in determining what effect(s) adult loss of BDNF expression in taste buds has on taste buds, gustatory nerve fibers and gustatory ganglion cells. Since I am interested in looking at the effect loss of BDNF expression has on the adult taste system and I do not want to disrupt the initial development of taste buds, I will use a tissue-specific conditional knockout mouse and knockout BDNF expression only in the tongues of adult mice. I can also denervate the taste buds in the tissue-specific conditional BDNF knockout mice to see whether nerve fibers will regenerate and reinnervate taste buds that no longer express BDNF. This aim will determine the role(s) of BDNF in adult mouse taste cells, without affecting the initial development of taste buds.