Juan T S, McNiece I K, Argento J M, Jenkins N A, Gilbert D J, Copeland N G, Fletcher F A
Department of Developmental Hematology, Amgen, Inc., Thousand Oaks, California 91320, USA.
Genomics. 1997 Feb 15;40(1):86-93. doi: 10.1006/geno.1996.4548.
Cloning of interleukin-1 beta converting enzyme (ICE) and Caenorhabditis elegans death protein CED-3 revealed the structural and functional homology between these two proteases. It also suggested the involvement of ICE-like cysteine proteases in apoptosis. Several CED-3- and ICE-like cysteine proteases have been described, including Nedd2/Ich-1, CPP32 beta, Tx, ICErel3, and Mch2. We have previously described a mouse ortholog of cysteine protease CPP32 beta that shares strong homology with ICE and CED-3. Here, we describe the cloning of mouse and human Casp7, another member of this family of cysteine proteases. Mouse Casp7 encodes a putative 340-amino-acid polypeptide that contains all the known conserved residues required for protease function, including the QACRG sequence, aspartic acid residues for internal cleavage sites, and the residues required for substrate binding. Three RNA variants of human Casp7 were also cloned. Amino acid sequence analysis indicated that Casp7 shared high homology with CPP32 beta/Casp3 and Mch2/Casp6. Northern blot analysis demonstrated that a 2.6-kb Casp7 mRNA was expressed in various tissues except brain. Mouse interspecific backcross mapping allowed localization of Casp7 to the distal region of mouse chromosome 19, linked to Mxi1, Adra2a, and Aop1.
白细胞介素-1β转换酶（ICE）和秀丽隐杆线虫死亡蛋白CED-3的克隆揭示了这两种蛋白酶之间的结构和功能同源性。这也提示了ICE样半胱氨酸蛋白酶参与细胞凋亡。已经描述了几种CED-3样和ICE样半胱氨酸蛋白酶，包括Nedd2/Ich-1、CPP32β、Tx、ICErel3和Mch2。我们之前描述了一种与ICE和CED-3具有高度同源性的小鼠半胱氨酸蛋白酶CPP32β的直系同源物。在此，我们描述了该半胱氨酸蛋白酶家族的另一个成员——小鼠和人Casp7的克隆。小鼠Casp7编码一种推定的340个氨基酸的多肽，其包含蛋白酶功能所需的所有已知保守残基，包括QACRG序列、内部切割位点的天冬氨酸残基以及底物结合所需的残基。还克隆了人Casp7的三种RNA变体。氨基酸序列分析表明，Casp7与CPP32β/Casp3和Mch2/Casp6具有高度同源性。Northern印迹分析表明，2.6 kb的Casp7 mRNA在除脑以外的各种组织中表达。小鼠种间回交图谱分析将Casp7定位到小鼠19号染色体的远端区域，与Mxi1、Adra2a和Aop1连锁。
