Ross A C
Department of Biochemistry, Medical College of Pennsylvania, Philadelphia 19129.
J Nutr. 1993 Feb;123(2 Suppl):346-50. doi: 10.1093/jn/123.suppl_2.346.
Substantial and exciting progress has been made in understanding the cytoplasmic metabolism and the nuclear functions of vitamin A. Keys to this understanding have come from studies of the plasma and cytoplasmic proteins that bind retinol and retinoic acid, thereby regulating retinoid concentration and specifying the enzymatic reactions through which retinol is absorbed, stored as esterified retinol or oxidized to retinoic acid. In the nucleus, the hormone-like activity of retinoic acid is transduced by a family of retinoic acid receptors that regulate a large number of retinoic acid-responsive genes. The coordination of cytoplasmic retinoid metabolism and the nuclear effects of retinoic acid or other retinoid metabolites is now recognized as critical to embryonic development and the control of cellular differentiation throughout life.
在理解维生素A的细胞质代谢和核功能方面已取得了重大且令人兴奋的进展。取得这一理解的关键来自对结合视黄醇和视黄酸的血浆和细胞质蛋白的研究，这些蛋白可调节类视黄醇浓度，并确定视黄醇被吸收、以酯化视黄醇形式储存或氧化为视黄酸所通过的酶促反应。在细胞核中，视黄酸的激素样活性由一类视黄酸受体传导，这些受体调节大量视黄酸反应性基因。细胞质类视黄醇代谢与视黄酸或其他类视黄醇代谢物的核效应之间的协调，现在被认为对胚胎发育以及终生细胞分化的控制至关重要。
