RGD Reference Report - Ca2+ binding protein-1 inhibits Ca2+ currents and exocytosis in bovine chromaffin cells. - Rat Genome Database

Send us a Message



Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   

Ca2+ binding protein-1 inhibits Ca2+ currents and exocytosis in bovine chromaffin cells.

Authors: Chen, ML  Chen, YC  Peng, IW  Kang, RL  Wu, MP  Cheng, PW  Shih, PY  Lu, LL  Yang, CC  Pan, CY 
Citation: Chen ML, etal., J Biomed Sci. 2008 Mar;15(2):169-81. Epub 2007 Oct 25.
RGD ID: 7207144
Pubmed: PMID:17960496   (View Abstract at PubMed)
DOI: DOI:10.1007/s11373-007-9217-8   (Journal Full-text)

Calcium binding protein-1 (CaBP1) is a calmodulin like protein shown to modulate Ca2+ channel activities. Here, we explored the functions of long and short spliced CaBP1 variants (L- and S-CaBP1) in modulating stimulus-secretion coupling in primary cultured bovine chromaffin cells. L- and S-CaBP1 were cloned from rat brain and fused with yellow fluorescent protein at the C-terminal. When expressed in chromaffin cells, wild-type L- and S-CaBP1s could be found in the cytosol, plasma membrane and a perinuclear region; in contrast, the myristoylation-deficient mutants were not found in the membrane. More than 20 and 70% of Na+ and Ca2+ currents, respectively, were inhibited by wild-type isoforms but not myristoylation-deficient mutants. The [Ca2+]( i ) response evoked by high K+ buffer and the exocytosis elicited by membrane depolarizations were inhibited only by wild-type isoforms. Neuronal Ca2+ sensor-1 and CaBP5, both are calmodulin-like proteins, did not affect N(+, Ca2+ currents, and exocytosis. When expressed in cultured cortical neurons, the [Ca2+]( i ) responses elicited by high-K+ depolarization were inhibited by CaBP1 isoforms. In HEK293T cells cotransfected with N-type Ca2+ channel and L-CaBP1, the current was reduced and activation curve was shifted positively. These results demonstrate the importance of CaBP1s in modulating the stimulus-secretion coupling in excitable cells.



Gene Ontology Annotations    Click to see Annotation Detail View

Biological Process

  
Object SymbolSpeciesTermQualifierEvidenceWithNotesSourceOriginal Reference(s)
Cabp1Ratnegative regulation of cell communication by electrical coupling  IDA  RGD 
Cabp1Ratnegative regulation of voltage-gated calcium channel activity  IDA  RGD 

Cellular Component

  
Object SymbolSpeciesTermQualifierEvidenceWithNotesSourceOriginal Reference(s)
Cabp1Ratperinuclear region of cytoplasm  IDA  RGD 

Objects Annotated

Genes (Rattus norvegicus)
Cabp1  (calcium binding protein 1)


Additional Information