Yoon S J, LeBlanc-Straceski J, Ward D, Krauter K, Kucherlapati R
Department of Molecular Genetics, Albert Einstein College of Medicine, Bronx, New York 10461.
Genomics. 1994 Dec;24(3):502-8. doi: 10.1006/geno.1994.1659.
Keratin proteins constitute intermediate filaments and are the major differentiation products of mammalian epithelial cells. The epithelial keratins are classified into two groups, type I and type II, and one member of each group is expressed in a given epithelial cell differentiation stage. Mutations in type I and type II keratin genes have now been implicated in three different human genetic disorders, epidermolysis bullosa simplex, epidermolytic hyperkeratosis, and epidermolytic palmoplantar keratoderma. Members of the type I keratins are mapped to human chromosome 17, and the type II keratin genes are mapped to chromosome 12. To understand the organization of the type II keratin genes on chromosome 12, we isolated several yeast artificial chromosomes carrying these keratin genes and examined them in detail. We show that eight already known type II keratin genes are located in a cluster at 12q13, and their relative organization reflects their evolutionary relationship. We also determined that a type I keratin gene, KRT18, is located next to its partner, KRT8, in this cluster. Careful examination of the cluster also revealed that there may be a number of additional keratin genes at this locus that have not been described previously.
角蛋白构成中间丝，是哺乳动物上皮细胞的主要分化产物。上皮角蛋白分为两组，I型和II型，每组中的一个成员在特定的上皮细胞分化阶段表达。I型和II型角蛋白基因的突变现已与三种不同的人类遗传疾病有关，即单纯性大疱性表皮松解症、表皮松解性角化过度症和表皮松解性掌跖角化病。I型角蛋白成员定位于人类17号染色体，II型角蛋白基因定位于12号染色体。为了了解12号染色体上II型角蛋白基因的组织情况，我们分离了几个携带这些角蛋白基因的酵母人工染色体并对其进行了详细研究。我们发现八个已知的II型角蛋白基因位于12q13的一个簇中，它们的相对组织反映了它们的进化关系。我们还确定一个I型角蛋白基因KRT18位于该簇中与其伴侣KRT8相邻的位置。对该簇的仔细检查还发现，该位点可能存在一些以前未描述过的额外角蛋白基因。
