Protein domains, catalytic activity, and subcellular distribution of mouse NTE-related esterase.
A mammalian family of lipid hydrolases, designated "patatin-like phospholipase domain containing (PNPLA)" recently has attracted attention. NTE-related esterase (NRE) as a member of PNPLA is an insulin-regulated lysophospholipase with homology to neuropathy target esterase (NTE). Mouse NRE (mNRE) has a predicted amino-terminal transmembrane region (TM), a putative regulatory (R) domain, and a hydrophobic catalytic (C) domain. In the current study, we described the expression of green fluorescent protein (GFP)-tagged constructs of mNRE and mutant proteins lacking the specific protein domains. Esterase assays indicated that neither the TM nor R-domain was essential for mNRE esterase activity, but the TM significantly contributed to its activity. Subcellular distribution showed that mNRE was anchored in ER via its TM domain and that its C-domain was associated with ER. Furthermore, experiments involving proteinase treatment revealed that most of mNRE molecule was exposed on the cytoplasmic face of ER membranes. Collectively, our results for the first time revealed the protein domains, catalytic activity, and subcellular location of mNRE and a simplified model for mNRE was proposed.
Chang
Ping-An
PA
Key Laboratory of Molecular Biology, College of Bio-information, Chongqing University of Posts and Telecommunications, Nan'an District, 400065 Chongqing, People's Republic of China. changpingan@yahoo.com.cn
Wang
Zhan-Xiang
ZX
Long
Ding-Xin
DX
Qin
Wen-Zhen
WZ
Wu
Yi-Jun
YJ
D000818:Animals; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain; D002462:Cell Membrane / Q000201:enzymology*; D002478:Cells, Cultured; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000201:enzymology*; D051379:Mice; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013347:Subcellular Fractions
D002265:Carboxylic Ester Hydrolases; D049452:Green Fluorescent Proteins; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; C530968:Pnpla7 protein, mouse