CLONING AND SEQUENCING OF A NOVEL MURINE LIVER CARBOXYLESTERASE CDNA

Carboxylesterases (EC 3.1.1.1) comprise a group of serine hydrolases w ith at least 20 genetically distinct loci in mice. Here, we describe d ifferential display PCR-based cloning of a cDNA, encoding a novel muri ne carboxylesterase termed ES-x, which was expressed predominantly in liver but also in kidney and lung, The cDNA of ES-x spanned a 2249-bp sequence with an open reading frame encoding 565 amino acids, includin g an N-terminal hydrophobic signal peptide which directs the synthesis into microsomal lumen and a C-terminal HVEL consensus sequence for re taining the protein in the lumen of the endoplasmic reticulum. The pre dicted amino acid sequence of ES-x exhibited 75% identity with rat liv er pi 6.1 esterase. We further demonstrate that feeding mice with diet s containing cholestyramine or sodium cholate increases mRNA-expressio n of ES-x in liver 2.5- to 3-fold. (C) 1998 Elsevier Science B.V.