Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.2.1.108 (
lactase
)
2,133
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The
cystic fibrosis transmembrane conductance regulator
(
CFTR
) channel is regulated by cAMP-dependent vesicle traffic and exocytosis to the apical membrane in some cell types, but this has not been demonstrated in the intestinal crypt. The distribution of
CFTR
,
lactase
(control), and fluid secretion were determined in rat jejunum after cAMP activation in the presence of nocodazole and primaquine to disrupt vesicle traffic.
CFTR
and
lactase
were localized by immunofluorescence, and surface proteins were detected by biotinylation of enterocytes. Immunoprecipitates from biotinylated and nonbiotinylated cells were analyzed by streptavidin detection and immunoblots. Immunolocalization confirmed a cAMP-dependent shift of
CFTR
but not
lactase
from a subapical compartment to the apical surface associated with fluid secretion that was reduced in the presence of primaquine and nocodazole. Analysis of immunoblots from immunoprecipitates after biotinylation revealed a 3.8 +/- 1.7-fold (P < 0.005) increase of surface-exposed
CFTR
after vasoactive intestinal peptide (VIP). These measurements provide independent corroboration supporting a role for vesicle traffic in regulating
CFTR
and cAMP-induced fluid transport in the intestine.
...
PMID:cAMP-dependent exocytosis and vesicle traffic regulate CFTR and fluid transport in rat jejunum in vivo. 1252 51
