title: Stimulation of intestinal basolateral membrane calcium-pump activity by recombinant synthetic calbindin-D9k and specific mutants.
abstract: Calcium transport by the Ca2(+)-pumping ATPase in rat duodenal basolateral-enriched membrane vesicles was stimulated by synthetic calbindin-D9k in a similar fashion to the purified natural protein. In order to elucidate the mechanism of this effect, various synthetic mutant proteins were studied. Proteins with modifications to the N-terminal Ca2(+)-binding domain, or to a cluster of negatively-charged surface residues had altered Ca2(+)-binding but these changes did not affect the stimulation of vesicular Ca2+ transport. It appears that these domains are not essential for the interaction between calbindin-D9k and the intestinal basolateral Ca2(+)-pump.
authors.affiliation: Gastroenterology Unit, United Medical School, London, U.K.
authors.forename: J R
authors.initials: JR
authors.lastname: Walters
authors.forename: A
authors.initials: A
authors.lastname: Howard
authors.forename: M V
authors.initials: MV
authors.lastname: Charpin
authors.forename: K C
authors.initials: KC
authors.lastname: Gniecko
authors.forename: P
authors.initials: P
authors.lastname: Brodin
authors.forename: E
authors.initials: E
authors.lastname: Thulin
authors.forename: S
authors.initials: S
authors.lastname: Forsén
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D064026:Calbindins; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004386:Duodenum / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009154:Mutation; D051381:Rats; D011994:Recombinant Proteins / Q000494:pharmacology; D064030:S100 Calcium Binding Protein G / Q000235:genetics / Q000494:pharmacology*
chemical_list: D064026:Calbindins; D015220:Calcium Channels; D011994:Recombinant Proteins; D064030:S100 Calcium Binding Protein G; C576508:S100g protein, rat; D002118:Calcium