P-CIP1, a novel protein that interacts with the cytosolic domain of peptidylglycine α-amidating monooxygenase, is associated with endosomes
P-CIP1, a novel protein that interacts with the cytosolic domain of peptidylglycine α-amidating monooxygenase, is associated with endosomes
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DOI：
10.1074/jbc.273.50.33524
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发表时间：
1998-12-11
影响因子：
4.8
通讯作者：
Milgram, SL
中科院分区：
文献类型：
--
作者：
Chen, LH;Johnson, RC;Milgram, SL
肽加工酶肽基甘氨酸酰胺化单加氧酶 (PAM) 的胞质结构域包含指导其在分泌和内体途径中运输的信号。使用酵母双杂交系统，Alam 等人。 （Alam, M. R.、Caldwell, B. D.、Johnson, R. C.、Darlington, D. N.、Mains, R. E. 和 Eipper, B. A. (1996) J. Biol. Chem. 271, 28636）鉴定了三种与 PAM 片段相互作用的蛋白质。含有这些靶向信号的胞质结构域。我们克隆了编码 PAM COOH 末端相互作用蛋白 1 (P-CIP1) 的大鼠和人类 cDNA，这两种 cDNA 均包含编码 435 个氨基酸的新型蛋白质的开放阅读框。 P-CIP1 蛋白在大鼠和人类之间高度保守（85% 同一性），但与 GenBank 数据库中的蛋白没有表现出显着的同源性。在体外，P-CIP1 与野生型 PAM-1 的胞质结构域相互作用，但不与突变型 PAM-1 蛋白相互作用，突变型 PAM-1 蛋白在内分泌细胞中表达时无法正确靶向。 P-CIP1 包含多个共有丝氨酸/苏氨酸磷酸化位点和一个预计在 COOH 末端形成卷曲螺旋的区域。当在内分泌细胞或成纤维细胞中表达时，P-CIP1在核周区域呈点状分布，但与转染的野生型PAM-1的分布没有显着重叠。P-CIP1的分布与分泌载体膜蛋白、内化德克萨斯红结合转铁蛋白和Rab11的分布表现出显着重叠。数据表明，P-CIP1 与循环内体途径中的囊泡相关，并且可能在调节整合膜 PAM 的运输中发挥作用。
The cytosolic domain of the peptide processing enzyme peptidylglycine cu-amidating monooxygenase (PAM) contains signals that direct its trafficking in the secretory and endosomal pathways. Using the yeast two-hybrid system, Alam et al. (Alam, M. R., Caldwell, B. D., Johnson, R. C., Darlington, D. N., Mains, R. E., and Eipper, B. A. (1996) J. Biol. Chem. 271, 28636) identified three proteins that interact with a fragment of the PAM. cytosolic domain containing these targeting signals. We cloned the rat and human cDNAs encoding PAM COOH-terminal interactor protein-1 (P-CIP1), Both cDNAs contain an open reading frame that encodes a novel protein of 435 amino acids. The P-CIP1 protein is highly conserved from rat to human (85% identity) but does not display significant homology to proteins in the GenBank data base. In vitro, P-CIP1 interacts with the cytosolic domain of wild type PAM-1, but does not interact with mutant PAM-1 proteins that fail to target correctly when expressed in endocrine cells. P-CIP1 contains multiple consensus serine/threonine phosphorylation sites and a region predicted to form a coiled-coil at the COOH terminus. When expressed in endocrine cells or fibroblasts, P-CIP1 is distributed in a punctate pattern in the perinuclear area but does not significantly overlap the distribution of transfected wild type PAM-1, The distribution of P-CIP1 displays significant overlap with the distribution of the Secretory carrier membrane proteins, internalized Texas Red-conjugated transferrin, and Rab11. The data suggest that P-CIP1 associates with vesicles in the recycling endosomal pathway, and may play a role in regulating the trafficking of integral membrane PAM.