This title appears in the Scientific Report :
2003
Please use the identifier:
http://dx.doi.org/10.1021/bi034025x in citations.
Please use the identifier: http://hdl.handle.net/2128/672 in citations.
Calcium-modulated guanylate cyclase transduction machinery in the photoreceptor-bipolar synaptic region
Calcium-modulated guanylate cyclase transduction machinery in the photoreceptor-bipolar synaptic region
Rod outer segment membrane guanylate cyclase (ROS-GC) transduction system is a central component of the Ca(2+)-sensitive phototransduction machinery. The system is composed of two parts: Ca(2+) sensor guanylate cyclase activating protein (GCAP) and ROS-GC. GCAP senses Ca(2+) impulses and inhibits th...
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Personal Name(s): | Venkataraman, V. |
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Duda, T. / Vardi, N. / Koch, K.-W. / Sharma, R. K. | |
Contributing Institute: |
Zelluläre Signalverarbeitung; IBI-1 |
Published in: | Biochemistry, 42 (2003) S. 5640 - 5648 |
Imprint: |
Columbus, Ohio
American Chemical Society
2003
|
Physical Description: |
5640 - 5648 |
PubMed ID: |
12741820 |
DOI: |
10.1021/bi034025x |
Document Type: |
Journal Article |
Research Program: |
Neurowissenschaften |
Series Title: |
Biochemistry
42 |
Subject (ZB): | |
Link: |
Get full text OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/672 in citations.
Rod outer segment membrane guanylate cyclase (ROS-GC) transduction system is a central component of the Ca(2+)-sensitive phototransduction machinery. The system is composed of two parts: Ca(2+) sensor guanylate cyclase activating protein (GCAP) and ROS-GC. GCAP senses Ca(2+) impulses and inhibits the cyclase. This operational feature of the cyclase is considered to be unique and exclusive in the phototransduction machinery. A combination of reconstitution, peptide competition, cross-linking, and immunocytochemical studies has been used in this study to show that the GCAP1/ROS-GC1 transduction system also exists in the photoreceptor synaptic (presynaptic) termini. Thus, the presence of this system and its linkage is not unique to the phototransduction machinery. A recent study has demonstrated that the photoreceptor-bipolar synaptic region also contains a Ca(2+)-stimulated ROS-GC1 transduction system [Duda, T., et al. (2002) EMBO J. 21, 2547-2556]. In this case, S100beta senses Ca(2+) and stimulates the cyclase. The inhibitory and stimulatory Ca(2+)-modulated ROS-GC1 sites are distinct. These findings allow the formation of a new topographic model of ROS-GC1 transduction. In this model, the catalytic module of ROS-GC1 at its opposite ends is flanked by GCAP1 and S100beta modules. GCAP1 senses the Ca(2+) impulse and inhibits the catalytic module; S100beta senses the impulse and stimulates the catalytic module. Thus, ROS-GC1 acts as a bimodal Ca(2+) signal transduction switch in the photoreceptor bipolar synapse. |