Differential expression and localization of the two calcium-binding
proteins mrp8 and mrp14 in pancreatic duct cell lines in relation to the
cystic fibrosis defect.
Fanjul, M., W. Renaud, M. Merten, O. Guy-Crotte, E. Hollande, and C.
Figarella.
Laboratoire de Biologie Cellulaire, Universit[acute]e Paul Sabatier, F-
31400 Toulouse and Groupe de Recherche sur les Glandes Exocrines, Faculte de
Medecine, 27, boulevard Jean Moulin, F-13385 Marseille Cedex 05.
APStracts 2:0030C, 1995.
A complex of two proteins : MRP8 ( also called cystic fibrosis antigen ) and
MRP 14, proteins known to be expressed in cells of myeloid origin, has been
shown to be present in higher amounts in the serum of cystic fibrosis
patients and heterozygotes compared to normal subjects. We demonstrated here
for the first time by dot blot analysis and by immunocytochemistry, the
expression and the presence of these S-100 calcium binding proteins in the
pancreatic cell lines CAPAN-1 and CFPAC-1, the latter provided from a patient
with cystic fibrosis. Moreover, using immunocytochemical methods, we showed
that the localization of MRP8 and MRP14 on the plasma membrane seems to be
restricted to the cells expressing a CFTR wild-type protein such as CAPAN-1
cells and CFPAC-1 cells transfected with a plasmid containing the non-mutated
CFTR gene (CFPAC-PLJ-CFTR-6 cells). In CFPAC-1 cells, immunoreactivity
remains in the cytoplasm throughout the stationary phase. We also showed an
increased level of the mRNAs of the two proteins in the CFPAC-1 cells
compared to those transfected with the non mutated CFTR. The demonstration of
a difference in the cellular localization of these two proteins as well as a
difference in their mRNA levels in the cell line of CF origin lets us to
assume the existence of a possible correlation in the expression of the MRPs
with that of the CFTR protein.
Received 30 November 1993; accepted in final form 10 November 1994
APS Manuscript Number C0602-3.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1994 The American Physiological Society.
Published in APStracts on 27 February 1995.