Calsyntenin-1, a Proteolytically Processed Postsynaptic Membrane Protein with a Cytoplasmic Calcium-Binding Domain

2001 ◽  
Vol 17 (1) ◽  
pp. 151-166 ◽  
Author(s):  
Lorenz Vogt ◽  
Sabine P. Schrimpf ◽  
Virginia Meskenaite ◽  
Renato Frischknecht ◽  
Jochen Kinter ◽  
...  
Keyword(s):  
Membrane Protein ◽  
Calcium Binding ◽  
Postsynaptic Membrane ◽  
Binding Domain ◽  
Cytoplasmic Calcium ◽  
Calcium Binding Domain

scholarly journals FRCaMP, a Red Fluorescent Genetically Encoded Calcium Indicator Based on Calmodulin from Schizosaccharomyces Pombe Fungus

2020 ◽  
Vol 22 (1) ◽  
pp. 111
Author(s):  
Oksana M. Subach ◽  
Natalia V. Barykina ◽  
Elizaveta S. Chefanova ◽  
Anna V. Vlaskina ◽  
Vladimir P. Sotskov ◽  
...  
Keyword(s):  
Schizosaccharomyces Pombe ◽  
Hela Cells ◽  
Calcium Binding ◽  
Dynamic Range ◽  
Spectral Characteristics ◽  
Binding Domain ◽  
Calcium Transients ◽  
Neuronal Cultures ◽  
Decay Kinetics ◽  
Calcium Binding Domain

Red fluorescent genetically encoded calcium indicators (GECIs) have expanded the available pallet of colors used for the visualization of neuronal calcium activity in vivo. However, their calcium-binding domain is restricted by calmodulin from metazoans. In this study, we developed red GECI, called FRCaMP, using calmodulin (CaM) from Schizosaccharomyces pombe fungus as a calcium binding domain. Compared to the R-GECO1 indicator in vitro, the purified protein FRCaMP had similar spectral characteristics, brightness, and pH stability but a 1.3-fold lower ΔF/F calcium response and 2.6-fold tighter calcium affinity with Kd of 441 nM and 2.4–6.6-fold lower photostability. In the cytosol of cultured HeLa cells, FRCaMP visualized calcium transients with a ΔF/F dynamic range of 5.6, which was similar to that of R-GECO1. FRCaMP robustly visualized the spontaneous activity of neuronal cultures and had a similar ΔF/F dynamic range of 1.7 but 2.1-fold faster decay kinetics vs. NCaMP7. On electrically stimulated cultured neurons, FRCaMP demonstrated 1.8-fold faster decay kinetics and 1.7-fold lower ΔF/F values per one action potential of 0.23 compared to the NCaMP7 indicator. The fungus-originating CaM of the FRCaMP indicator version with a deleted M13-like peptide did not interact with the cytosolic environment of the HeLa cells in contrast to the metazoa-originating CaM of the similarly truncated version of the GCaMP6s indicator with a deleted M13-like peptide. Finally, we generated a split version of the FRCaMP indicator, which allowed the simultaneous detection of calcium transients and the heterodimerization of bJun/bFos interacting proteins in the nuclei of HeLa cells with a ΔF/F dynamic range of 9.4 and a contrast of 2.3–3.5, respectively.

scholarly journals Mutagenesis of the fourth calcium-binding domain of yeast calmodulin

1993 ◽  
Vol 268 (18) ◽  
pp. 13267-13273
Author(s):  
I. Matsuura ◽  
E. Kimura ◽  
K. Tai ◽  
M. Yazawa
Keyword(s):  
Calcium Binding ◽  
Binding Domain ◽  
Calcium Binding Domain

A novel GSN variant outside the G2 calcium‐binding domain associated with Amyloidosis of the Finnish type

2021 ◽  
Author(s):  
Sean Mullany ◽  
Emmanuelle Souzeau ◽  
Sonja Klebe ◽  
Tiger Zhou ◽  
Lachlan S. W. Knight ◽  
...  
Keyword(s):  
Calcium Binding ◽  
Binding Domain ◽  
Finnish Type ◽  
Calcium Binding Domain

scholarly journals Glanzmann thrombasthenia due to a two amino acid deletion in the fourth calcium-binding domain of alpha IIb: demonstration of the importance of calcium-binding domains in the conformation of alpha IIb beta 3

Blood ◽  
1996 ◽  
Vol 88 (1) ◽  
pp. 167-173 ◽  
Author(s):  
RB Basani ◽  
G Vilaire ◽  
SJ Shattil ◽  
MA Kolodziej ◽  
JS Bennett ◽  
...  
Keyword(s):  
Amino Acid ◽  
Cell Surface ◽  
Calcium Binding ◽  
Binding Domain ◽  
In Vitro Mutagenesis ◽  
Amino Acid Deletion ◽  
Glanzmann Thrombasthenia ◽  
Binding Domains ◽  
Intracellular Processing ◽  
Calcium Binding Domain

The integrin alpha IIb beta 3, a calcium-dependent heterodimer, plays a critical role in platelet aggregation. The alpha IIb subunit of the heterodimer contains four highly conserved putative calcium-binding domains in its extracellular portion. During studies of the molecular basis of Glanzmann thrombasthenia in a child of mixed Caucasian background whose platelets expressed little alpha IIb beta 3 on their surface, we found the patient heterozygous for a two amino acid deletion in the fourth alpha IIb calcium-binding domain. When this alpha IIb mutant was expressed in COS-1 cells, we found that the deletion did not interfere with the assembly of alpha IIb beta 3 heterodimers, but altered their conformation such that they were neither recognized by the heterodimer-specific antibody A2A9 nor able to undergo further intracellular processing or transport to the cell surface. These results suggest that the calcium-binding domains in alpha IIb play an important role maintaining the overall conformation of alpha IIb beta 3. To confirm this suggestion, we deleted each of the four 12 amino acid calcium-binding domains in alpha IIb by in vitro mutagenesis and expressed the mutants along with beta 3 in COS-1 cells. Each construct formed a heterodimer with beta 3, but none of the heterodimers interacted with A2A9 or underwent further intracellular processing. These data indicate that the calcium-binding domains in alpha IIb are not involved in alpha IIb beta 3 heterodimer formation, but their presence is required for the intracellular transport of alpha IIb beta 3 to the cell surface.

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