scholarly journals Chromaffin Granule Amine Transporter

2020 ◽  
Author(s):  
Keyword(s):  
Chromaffin Granule

scholarly journals Phosphatidylinositol-specific phospholipase C activity of chromaffin granule-binding proteins.

1985 ◽  
Vol 260 (12) ◽  
pp. 7171-7173 ◽  
Author(s):  
C E Creutz ◽  
L G Dowling ◽  
E M Kyger ◽  
R C Franson
Keyword(s):  
Phospholipase C ◽  
Binding Proteins ◽  
Chromaffin Granule

scholarly journals Chromogranin A, the major lumenal protein in chromaffin granules, controls fusion pore expansion

2018 ◽  
Vol 151 (2) ◽  
pp. 118-130 ◽  
Author(s):  
Prabhodh S. Abbineni ◽  
Mary A. Bittner ◽  
Daniel Axelrod ◽  
Ronald W. Holz
Keyword(s):  
Plasma Membrane ◽  
Small Molecules ◽  
Chromogranin A ◽  
Chromaffin Cells ◽  
Fusion Pore ◽  
Chromaffin Granules ◽  
Chromaffin Granule ◽  
Chromogranin B ◽  
Tissue Plasminogen ◽  
Pore Expansion

Upon fusion of the secretory granule with the plasma membrane, small molecules are discharged through the immediately formed narrow fusion pore, but protein discharge awaits pore expansion. Recently, fusion pore expansion was found to be regulated by tissue plasminogen activator (tPA), a protein present within the lumen of chromaffin granules in a subpopulation of chromaffin cells. Here, we further examined the influence of other lumenal proteins on fusion pore expansion, especially chromogranin A (CgA), the major and ubiquitous lumenal protein in chromaffin granules. Polarized TIRF microscopy demonstrated that the fusion pore curvature of granules containing CgA-EGFP was long lived, with curvature lifetimes comparable to those of tPA-EGFP–containing granules. This was surprising because fusion pore curvature durations of granules containing exogenous neuropeptide Y-EGFP (NPY-EGFP) are significantly shorter (80% lasting <1 s) than those containing CgA-EGFP, despite the anticipated expression of endogenous CgA. However, quantitative immunocytochemistry revealed that transiently expressed lumenal proteins, including NPY-EGFP, caused a down-regulation of endogenously expressed proteins, including CgA. Fusion pore curvature durations in nontransfected cells were significantly longer than those of granules containing overexpressed NPY but shorter than those associated with granules containing overexpressed tPA, CgA, or chromogranin B. Introduction of CgA to NPY-EGFP granules by coexpression converted the fusion pore from being transient to being longer lived, comparable to that found in nontransfected cells. These findings demonstrate that several endogenous chromaffin granule lumenal proteins are regulators of fusion pore expansion and that alteration of chromaffin granule contents affects fusion pore lifetimes. Importantly, the results indicate a new role for CgA. In addition to functioning as a prohormone, CgA plays an important role in controlling fusion pore expansion.

Characterization of Calcium-Dependent Chromaffin Granule Binding Proteins

1987 ◽  
Vol 493 (1 Cellular and) ◽  
pp. 489-492 ◽  
Author(s):  
CARL E. CREUTZ ◽  
WILLIAM H. MARTIN ◽  
WILLIAM J. ZAKS ◽  
DEBRA S. DRUST ◽  
HELEN C. HAMMAN
Keyword(s):  
Binding Proteins ◽  
Chromaffin Granule ◽  
Calcium Dependent
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