In this article, we report the nucleotide sequence of the cDNA encoding an isoform of bile-salt-dependent lipase (BSDL) expressed by human hepatoma cells. The BSDL is a 100-kDa glycoprotein normally expressed by the human pancreas. Using a polyclonal antibody raised against an internal peptide located between Ile327 and Glu350 of the human pancreatic BSDL, we have immunodetected an isoform of human pancreatic BSDL, with an apparent molecular mass of about 62 kDa. This isoform of BSDL was mainly associated with the cytosol of a human hepatoma cell line (HepG2), the remaining protein being found in the microsome fraction. In addition, esterolytic activity on p-nitrophenyl hexanoate measured in microsomes and cytosol appeared very low and was weakly stimulated by bile salts, such as taurocholate. In contrast to human pancreatic BSDL, which is secreted as a component of pancreatic juice, this isoform appeared to be retained in the HepG2 cells. Reverse transcription, followed by PCR and amplification, performed on RNA extracted from HepG2 cells using specific primers hybridizing to the sequence coding for the entire normal human pancreatic BSDL, allowed us to amplify a 1.7-kb transcript that appeared to be 0.5 kb shorter than the transcript of the pancreatic enzyme (2.2 kb). From the sequence of the transcript thus obtained, a protein with a molecular mass of 62 kDa might be predicted, which is in good agreement with the size of the isoform of BSDL immunodetected in HepG2 cells. The N-terminal amino-acid sequence, deduced from the 1.7-kb transcript sequence, matched that of the pancreatic BSDL. However, the C-terminal domain appeared truncated, bearing only a single mucin-like sequence compared with sixteen for the human pancreatic BSDL. The actual intracellular function of this human BSDL hepatoma isoform remains to be elucidated.
Skip Nav Destination
Article navigation
August 1999
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Research Article|
August 10 1999
Immunodetection and molecular cloning of a bile-salt-dependent lipase isoform in HepG2 cells
Alain VÉRINE;
Alain VÉRINE
1
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
1To whom correspondence should be addressed (e-mail Alain.Verine@medecine.univ-mrs.fr).
Search for other works by this author on:
Nadine BRUNEAU;
Nadine BRUNEAU
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
Search for other works by this author on:
Anne VALETTE;
Anne VALETTE
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
Search for other works by this author on:
Josette LE PETIT-THEVENIN;
Josette LE PETIT-THEVENIN
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
Search for other works by this author on:
Eric PASQUALINI;
Eric PASQUALINI
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
Search for other works by this author on:
Dominique LOMBARDO
Dominique LOMBARDO
1INSERM U 260, Unité de Recherches de Physiopathologie des Régulations Hormono-Nutritionnelles, Faculté de Médecine, 27 Bld Jean Moulin, 13385 Marseille Cedex 05, France
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
February 02 1999
Revision Received:
April 27 1999
Accepted:
June 04 1999
Online ISSN: 1470-8728
Print ISSN: 0264-6021
The Biochemical Society, London © 1999
1999
Biochem J (1999) 342 (1): 179–187.
Article history
Received:
February 02 1999
Revision Received:
April 27 1999
Accepted:
June 04 1999
Citation
Alain VÉRINE, Nadine BRUNEAU, Anne VALETTE, Josette LE PETIT-THEVENIN, Eric PASQUALINI, Dominique LOMBARDO; Immunodetection and molecular cloning of a bile-salt-dependent lipase isoform in HepG2 cells. Biochem J 15 August 1999; 342 (1): 179–187. doi: https://doi.org/10.1042/bj3420179
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Captcha Validation Error. Please try again.