Fujita H, Furuyama K, Sasaki T, Takagawa M
Department of Applied Physiology and Molecular Biology, Tohoku University School of Medicine.
Nihon Rinsho. 1995 Jun;53(6):1339-48.
It is generally accepted that the major organs producing heme are erythroid cells and the liver. delta-Aminolevulinate synthase (ALAS) plays the key role to regulate heme biosynthesis in the liver as well as in erythroid cells. In the liver, nonspecific (or housekeeping) isozyme of ALAS (ALAS-N) is expressed to be regulated by its end product, heme, in the negative feedback manner. Not only erythroid isozyme of ALAS (ALAS-E) but also ALAS-N is expressed in erythroid tissues, and are regulated by distinctive manners. For example, heme regulates ALAS-N and ALAS-E in the negative and in the positive feedback manner, respectively. In this article, we describe the molecular mechanisms to regulate heme biosynthesis not only in the liver but also in erythroid cells.
一般认为，产生血红素的主要器官是红细胞和肝脏。δ-氨基乙酰丙酸合酶（ALAS）在肝脏和红细胞中对血红素生物合成的调节起着关键作用。在肝脏中，ALAS的非特异性（或管家）同工酶（ALAS-N）以负反馈方式表达并受其终产物血红素调节。不仅ALAS的红细胞同工酶（ALAS-E），而且ALAS-N也在红细胞组织中表达，并以不同方式调节。例如，血红素分别以负反馈和正反馈方式调节ALAS-N和ALAS-E。在本文中，我们描述了不仅在肝脏而且在红细胞中调节血红素生物合成的分子机制。
