Global ETD Search

1	Syntaxin-1A Inhibits the KATP Channel Through Interaction with Distinct Sites Along the Nucleotide-binding Folds of Sulfonylurea Receptor 1 Chang, Nathan 13 January 2010 (has links) The KATP channel is a key regulator of the pancreatic β-cell, effectively linking metabolic status to electrical activity. Syntaxin-1A has been previously reported by our lab to both bind and inhibit the KATP channel via the nucleotide-binding folds (NBFs). The purpose of this thesis project was to elucidate the precise regions within the NBFs responsible for the Syn-1A- KATP interaction. In vitro binding assays revealed that Syn-1A associates with the Walker domains of both NBF1 and NBF2. Furthermore, site directed mutagenesis of the conserved lysine in Walker A of both NBFs abolishes Syn-1A affinity for this region. Electrophysiological recordings indicate that channel inhibition was mediated primarily through interaction with NBF1-Walker B and both Walkers of NBF2. Based on these results, we propose a model by which Syn-1A acts as an inhibitory clamp on the KATP channel, effectively buffering minor fluctuations in ATP/ADP concentration to prevent unnecessary channel activity. Syntaxin-1A KATP nucleotide-binding folds ATP/ADP 0719
2	Syntaxin-1A Inhibits the KATP Channel Through Interaction with Distinct Sites Along the Nucleotide-binding Folds of Sulfonylurea Receptor 1 Chang, Nathan 13 January 2010 (has links) The KATP channel is a key regulator of the pancreatic β-cell, effectively linking metabolic status to electrical activity. Syntaxin-1A has been previously reported by our lab to both bind and inhibit the KATP channel via the nucleotide-binding folds (NBFs). The purpose of this thesis project was to elucidate the precise regions within the NBFs responsible for the Syn-1A- KATP interaction. In vitro binding assays revealed that Syn-1A associates with the Walker domains of both NBF1 and NBF2. Furthermore, site directed mutagenesis of the conserved lysine in Walker A of both NBFs abolishes Syn-1A affinity for this region. Electrophysiological recordings indicate that channel inhibition was mediated primarily through interaction with NBF1-Walker B and both Walkers of NBF2. Based on these results, we propose a model by which Syn-1A acts as an inhibitory clamp on the KATP channel, effectively buffering minor fluctuations in ATP/ADP concentration to prevent unnecessary channel activity. Syntaxin-1A KATP nucleotide-binding folds ATP/ADP 0719
3	The Regulatory Role of Syntaxin 1 N-terminal Conformation in Vesicle Priming and Exocytosis / Die Regulation der Vesikelreifung und -Freisetzung durch Syntaxin 1 Rah, Jong-Cheol 02 November 2004 (has links) No description available. 590 Tiere (Zoologie) Mathematics and Computer Science hippocampus CNS neuron neurotransmitter exocytosis SNARE syntaxin 1A conformation hippocampus CNS neuron neurotransmitter exocytosis SNARE syntaxin 1A conformation 42.12
4	Syntaxin-1A Inhibits Cardiac ATP-Sensitive Potassium Channels by Direct Interaction with Distinct Domains within Sulphonylurea Receptor 2A Nucleotide-Binding Folds Chao, Christin Chih Ting 13 January 2010 (has links) KATP channels couple cell metabolic status to the membrane excitability by sensing the cytoplasmic ATP/ADP ratio. Present studies examined how conserved motifs (Walker A (WA), signature sequence (L), and Walker B (WB)) within each NBF of SUR2A bind to Syn-1A to affect its actions on cardiac KATP channels. In vitro binding experiments illustrated that Syn-1A binds cardiac SUR2A at WA and L of NBF-1 and WA, L, and WB of NBF-2. Electrophysiology experiments on stably expressing SUR2A/Kir6.2 cell-lines showed that only L and WB of NBF-1 and all three NBF-2 motifs could abrogate the inhibitory effect of Syn-1A on SUR2A/KATP channels. These results lead me to hypothesize that more independent motif in NBF-2 can bind and abrogate Syn-1A’s inhibition than NBF-1 on SUR2A/KATP channels. A corollary postulate is that Syn-1A acts as a scaffold to secure the NBF-1 and -2 in dimer conformation required for SUR2A to modulate Kir6.2 gating. Syntaxin-1A ATP-sensitive potassium channel sulfonylurea receptor SNARE Kir6.2 SUR2A 0719
5	Syntaxin-1A Inhibits Cardiac ATP-Sensitive Potassium Channels by Direct Interaction with Distinct Domains within Sulphonylurea Receptor 2A Nucleotide-Binding Folds Chao, Christin Chih Ting 13 January 2010 (has links) KATP channels couple cell metabolic status to the membrane excitability by sensing the cytoplasmic ATP/ADP ratio. Present studies examined how conserved motifs (Walker A (WA), signature sequence (L), and Walker B (WB)) within each NBF of SUR2A bind to Syn-1A to affect its actions on cardiac KATP channels. In vitro binding experiments illustrated that Syn-1A binds cardiac SUR2A at WA and L of NBF-1 and WA, L, and WB of NBF-2. Electrophysiology experiments on stably expressing SUR2A/Kir6.2 cell-lines showed that only L and WB of NBF-1 and all three NBF-2 motifs could abrogate the inhibitory effect of Syn-1A on SUR2A/KATP channels. These results lead me to hypothesize that more independent motif in NBF-2 can bind and abrogate Syn-1A’s inhibition than NBF-1 on SUR2A/KATP channels. A corollary postulate is that Syn-1A acts as a scaffold to secure the NBF-1 and -2 in dimer conformation required for SUR2A to modulate Kir6.2 gating. Syntaxin-1A ATP-sensitive potassium channel sulfonylurea receptor SNARE Kir6.2 SUR2A 0719

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