Slominski A, Costantino R, Howe J, Moellmann G
Department of Microbiology and Immunology, Albany Medical College, NY 12208.
Anticancer Res. 1991 Jan-Feb;11(1):257-62.
Variants of the Bomirski family of hamster melanomas whose proliferative rates differ inversely with the genetically determined degree of melanogenesis were probed for two proteins critical in melanogenesis: tyrosinase and catalase-B (gp 75). The parental black tumor Ma contained both proteins in abundance. The amelanotic variant Ab, inducible in culture with L-tyrosine or L-dopa to form melanosomes and to melanize, had minimal tyrosinase, despite high levels of (tyr)mRNA, and no gp 75. Variant MI, hypomelanotic despite abundant tyrosinase, and synthesizing predominantingly pheo-(red) melanin, expressed barely detectable gp 75. These findings suggest a regulatory control of melanogenesis distal to (tyr)mRNA and strengthen the hypothesis that in vivo tyrosinase without catalase-B favors pheo- over eumelanogenesis.
对博米尔斯基家族仓鼠黑色素瘤的变种进行了研究，这些变种的增殖率与基因决定的黑色素生成程度呈反比，研究针对黑色素生成过程中至关重要的两种蛋白质：酪氨酸酶和过氧化氢酶-B（gp 75）。亲本黑色肿瘤Ma富含这两种蛋白质。无黑色素变种Ab在培养中可被L-酪氨酸或L-多巴诱导形成黑素小体并发生黑色素沉着，尽管（tyr）mRNA水平很高，但酪氨酸酶含量极低，且没有gp 75。变种MI尽管酪氨酸酶丰富但黑色素生成不足，且主要合成棕褐（红色）黑色素，其表达的gp 75几乎检测不到。这些发现表明在（tyr）mRNA水平远端存在对黑色素生成的调控，并且强化了这样一种假说，即在体内没有过氧化氢酶-B的酪氨酸酶有利于棕褐黑色素生成而非真黑色素生成。
