Goto Masanori, Hojo Masato, Ando Mitsushige, Kita Aya, Kitagawa Masashi, Ohtsuka Toshiyuki, Kageyama Ryoichiro, Miyamoto Susumu
Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan; Department of Neurosurgery, Shiga Medical Center for Adults, 5-4-30 Moriyama, Moriyama, Shiga 524-8524, Japan.
Brain Res. 2015 Nov 2;1625:206-17. doi: 10.1016/j.brainres.2015.08.045. Epub 2015 Sep 6.
The pituitary gland is a critical endocrine organ regulating diverse physiological functions, including homeostasis, metabolism, reproduction, and growth. It is composed of two distinct entities: the adenohypophysis, including the anterior and intermediate lobes, and the neurohypophysis known as the posterior lobe. The neurohypophysis is composed of pituicytes (glial cells) and axons projected from hypothalamic neurons. The adenohypophysis derives from Rathke's pouch, whereas the neurohypophysis derives from the infundibulum, an evagination of the ventral diencephalon. Molecular mechanisms of adenohypophysis development are much better understood, but little is known about mechanisms that regulate neurohypophysis development. Hes genes, known as Notch effectors, play a crucial role in specifying cellular fates during the development of various tissues and organs. Here, we report that the ventral diencephalon fails to evaginate resulting in complete loss of the posterior pituitary lobe in Hes1(-/-); Hes5(+/-) mutant embryos. In these mutant mice, progenitor cells are differentiated into neurons at the expense of pituicytes in the ventral diencephalon. In the developing neurohypophysis, the proliferative zone is located at the base of the infundibulum. Thus, Hes1 and Hes5 modulate not only maintenance of progenitor cells but also pituicyte versus neuron fate specification during neurohypophysis development.
垂体是一个关键的内分泌器官，调节多种生理功能，包括体内平衡、新陈代谢、生殖和生长。它由两个不同的部分组成：腺垂体，包括前叶和中间叶，以及神经垂体，即后叶。神经垂体由垂体细胞（神经胶质细胞）和从下丘脑神经元投射而来的轴突组成。腺垂体起源于拉特克囊，而神经垂体起源于漏斗，即腹侧间脑的一个突起。腺垂体发育的分子机制已被更好地理解，但调节神经垂体发育的机制却知之甚少。Hes基因作为Notch效应器，在各种组织和器官发育过程中决定细胞命运方面发挥着关键作用。在此，我们报告在Hes1(-/-); Hes5(+/-)突变胚胎中，腹侧间脑未能突出，导致垂体后叶完全缺失。在这些突变小鼠中，腹侧间脑的祖细胞分化为神经元，而牺牲了垂体细胞。在发育中的神经垂体中，增殖区位于漏斗底部。因此，Hes1和Hes5不仅调节祖细胞的维持，还调节神经垂体发育过程中垂体细胞与神经元命运的决定。
