SEQUENCE ANALYSES AND INTERSPECIES COMPARISONS OF 3 NOVEL HUMAN PROTEASOMAL SUBUNITS, HSN3, HSC7-I AND HSC10-II, CONFINE POTENTIAL PROTEOLYTIC ACTIVE-SITE RESIDUES
SEQUENCE ANALYSES AND INTERSPECIES COMPARISONS OF 3 NOVEL HUMAN PROTEASOMAL SUBUNITS, HSN3, HSC7-I AND HSC10-II, CONFINE POTENTIAL PROTEOLYTIC ACTIVE-SITE RESIDUES
复制标题
DOI：
10.1016/0167-4781(94)90060-4
复制
发表时间：
1994-10-18
期刊：
影响因子：
--
通讯作者：
ICHIHARA, A
中科院分区：
文献类型：
--
作者：
NOTHWANG, HG;TAMURA, T;ICHIHARA, A
蛋白酶体在由不同的多种蛋白水解活性介导的蛋白质周转的非溶酶体途径中起主要作用。它们活性中心残基的鉴定对于阐明它们的催化机理是重要的。本文报道了人蛋白酶体亚基HsN 3、HsC 7-I和HsC 10-II的核苷酸序列，它们分别编码264、201和205个氨基酸残基的蛋白质，计算分子量分别为29192、22836和22931。序列比较表明，这三种蛋白质都属于β-型超家族，它们是报告参与肽基-谷氨酰-肽水解、胰凝乳蛋白酶样和胰蛋白酶样活性的亚基的人类对应物。各种物种的推定的催化活性亚基的比对揭示了高度保守的氨基酸段内的几个家族特异性保守的丝氨酸残基。基于定位和疏水性，这些氨基酸残基作为活性位点和底物结合位点候选人的作用进行了讨论。
Proteasomes play a major role in non-lysosomal pathways of protein turnover mediated by distinct multiple proteolytic activities. Identification of their active-site residues is important for elucidating their catalytic mechanisms. Here we report the nucleotide sequences of three human proteasomal subunits, HsN3, HsC7-I and HsC10-II, coding for proteins with 264, 201 and 205 amino acid residues with calculated molecular weights of 29192, 22836 and 22931, respectively. Sequence comparison showed that all three proteins belong to the beta-type superfamily and that they are the human counterparts of subunits reported to participate in the peptidyl-glutamyl-peptide hydrolyzing, chymotrypsin-like and trypsin-like activity of this complex. Alignments of the putative catalytically active subunits of various species revealed several family-specifically conserved serinyl residues within highly conserved amino acid stretches. Based on localization and hydrophobicity, the roles of these amino acid residues as active site and substrate binding site candidates are discussed.