Gahl W A
Human Genetics Branch, National Institute of Child Health and Human Development, Bethesda, Md.
Enzyme. 1987;38(1-4):154-60. doi: 10.1159/000469201.
Two lysosomal storage diseases are now known to result from impaired transport of small molecules across the lysosomal membrane. In cystinosis, the disulfide amino acid, cystine, accumulates and in free sialic acid storage disorders, N-acetylneuraminic acid is stored. The lysosomal cystine carrier exhibits saturability, counter-transport, temperature dependence, and stereospecificity; it is highly specific for molecules resembling cystine. Less is known about sialic acid transport, but its temperature dependence and deficiency in certain autosomal-recessive human mutations strongly suggests that it is a carrier-mediated process. Cystine and sialic acid serve as prototypes for amino acids and sugars transported by specific lysosomal membrane carriers, whose impairment results in lysosomal storage disorders.
现已明确，两种溶酶体贮积病是由小分子跨溶酶体膜转运受损所致。在胱氨酸病中，二硫氨基酸胱氨酸会蓄积，而在游离唾液酸贮积症中，N - 乙酰神经氨酸会被储存。溶酶体胱氨酸载体具有饱和性、反向转运、温度依赖性和立体特异性；它对类似胱氨酸的分子具有高度特异性。关于唾液酸转运的了解较少，但它的温度依赖性以及在某些常染色体隐性人类突变中的缺乏强烈表明这是一个载体介导的过程。胱氨酸和唾液酸可作为特定溶酶体膜载体转运的氨基酸和糖类的原型，这些载体的损伤会导致溶酶体贮积病。
