STRUCTURE-FUNCTION RELATIONSHIPS OF LYSOSOMAL ENZYMES

β-氨基己糖苷酶已成为理解 溶酶体酶生物学 为了进一步了解 氨基己糖苷酶系统，我们已经分离出人类基因组克隆，覆盖了 编码酶α链的整个基因。 这些克隆人 通过限制性酶切图谱、Southern印迹和DNA 测序 α链基因跨越35个DNA内切酶， 分为14个外显子 内含子的位置与潜在的蛋白质相匹配 加工位点，表明基因结构与蛋白质的相关性 结构 该基因的启动子区含有常规的“TATA”， 和CAAT图案 我们还分离了编码 氨基己糖苷酶的β链。 这些克隆的序列分析 表明与α链具有广泛的结构同源性， 在两个亚基的氨基末端存在显著差异。

Beta-hexosaminidase has become a paradigm for the understanding of lysosomal enzyme biology. In order to gain further insight into the hexosaminidase system, we have isolated human genomic clones covering the entire gene encoding the alpha chain of the enzyme. These clones have been characterized by restriction mapping, Southern blotting and DNA sequencing. The alpha chain gene spans 35 kilobases of DNA and is split into 14 exons. The position of introns matches potential protein processing sites, indicating a correlation of gene structure with protein structure. The promoter region of this gene contains conventional "TATA" and "CAAT" motifs. We have also isolated cDNA and genomic clones encoding the beta chain of hexosaminidase. Sequence analysis of these clones indicate extensive structural homology with the alpha chain with significant differences at the amino-termini of the two subunits.