ABCC8 p.Cys717Ser

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PMID: 19284878 [PubMed] Kawano T et al: "Nitric oxide activates ATP-sensitive potassium channels in mammalian sensory neurons: action by direct S-nitrosylation."
No. Sentence Comment
189 We therefore focused on this cysteine residue, and examined the effect of mutating C717 to serine (C717S) on the sensitivity of the cloned SUR1/Kir6.2 channel to NO.
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ABCC8 p.Cys717Ser 19284878:189:99
status: NEW
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190 A patch containing recombinant SUR1-C717S/Kir6.2 channels, also showed marked current increases when excised into a low [ATP]i (0.1 μM) solution (Figure 9A).
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ABCC8 p.Cys717Ser 19284878:190:36
status: NEW
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192 The ATP-sensitivity of SUR1-C717S/Kir6.2 channels (IC50 = 13.1 μM, n = 7) was not significantly different from that of wild type SUR1/Kir6.2 channels (IC50 = 11.6 μM, n = 7).
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ABCC8 p.Cys717Ser 19284878:192:28
status: NEW
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ABCC8 p.Cys717Ser 19284878:192:36
status: NEW
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193 Similar to the response of wild type SUR1/Kir6.2 channels, bath application of 1 mM SNAP significantly activated the SUR1-C717S/Kir6.2 channel in the presence of 1 mM [ATP]i. However SNAP was significantly less potent in activating the SUR1-C717S/Kir6.2 channel compared with the wild-type SUR1/Kir6.2 channel (n = 8, p < 0.02 vs. wild type; Figure 9C).
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ABCC8 p.Cys717Ser 19284878:193:122
status: NEW
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ABCC8 p.Cys717Ser 19284878:193:241
status: NEW
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194 SNAP-induced SUR1-C717S/Kir6.2 channel activation was reversed by DTT (5 mM) (n = 7).
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ABCC8 p.Cys717Ser 19284878:194:18
status: NEW
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ABCC8 p.Cys717Ser 19284878:194:28
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195 In addition to C717S, we further examined the activating effects of NO after mutating the cysteine residues within NBD1 and NBD2 to serine, including those cysteine residues adjacent to C717 within NBD1 (C806S), and all three cysteine residues within NBD2 (C1378, C1446, C1491).
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ABCC8 p.Cys717Ser 19284878:195:15
status: NEW
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ABCC8 p.Cys717Ser 19284878:195:122
status: NEW
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197 Among these mutants, only SUR1-C717S/Kir6.2 channels significantly affected NO-sensitivity compared with wild type SUR1/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:197:18
status: NEW
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ABCC8 p.Cys717Ser 19284878:197:31
status: NEW
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213 Figure 9 (see legend on next page) A B SUR1-C717/Kir6.2 Wild type SUR1/Kir6.2 SUR1-C717S/Kir6.2 Relativechannelactivity ATP 1 μM ATP 1 mM 5 pA 200 ms [ATP]i (μM) C SNAP ATP 1 mM SNAP + DTT ATP 1 mM (ATP 1 mM) SNAP (+) Relative channel activity wt SUR1 SUR1-C717S SUR1-C806S SUR1-C1378S SUR1-C1446S SUR1-C1491S wt SUR1 SUR1-C717S SUR1-C806S SUR1-C1378S SUR1-C1446S SUR1-C1491S control D SUR1-C717/Kir6.2 5 pA 200 ms * Although the sGC/cGMP/PKG pathway mediates NO regulation of KATP channels in cardiomyocytes, vascular and non-vascular smooth muscle cells, and pancreatic β cells [52-56], this is not the case in DRG neurons.
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ABCC8 p.Cys717Ser 19284878:213:83
status: NEW
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ABCC8 p.Cys717Ser 19284878:213:269
status: NEW
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ABCC8 p.Cys717Ser 19284878:213:335
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235 (A) Representative traces of currents via SUR1-C717S/Kir6.2 channels in inside-out patches at -60 mV holding potential.
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ABCC8 p.Cys717Ser 19284878:235:47
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236 Bath application of ATP (1 mM) inhibited SUR1-C717S/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:236:46
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237 Arrows indicate closed channel state. (B) Concentration-response relationship curves between [ATP]i and relative NPo values for wild-type SUR1/Kir6.2 or SUR1-C717S/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:237:158
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240 (C) Representative current traces of SUR1-C717S/ Kir6.2 channel currents in inside-out patches at -60 mV holding potential. In the presence of 1 mM [ATP]i, bath application of SNAP (1 mM) activated SUR1-C717S/Kir6.2 channel, but less than wild-type SUR1/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:240:42
status: NEW
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ABCC8 p.Cys717Ser 19284878:240:46
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301 Point mutation of cysteine at position 717 (C717), C806, C1378, C1446, and C1491 within SUR1 to serine (C717S, C806S, C1378S, C1446S, and C1491S) was performed by using the Site-Directed Mutagenesis system (Invitrogen Corp.).
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ABCC8 p.Cys717Ser 19284878:301:104
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191 We therefore focused on this cysteine residue, and examined the effect of mutating C717 to serine (C717S) on the sensitivity of the cloned SUR1/Kir6.2 channel to NO.
X
ABCC8 p.Cys717Ser 19284878:191:99
status: NEW
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196 However SNAP was significantly less potent in activating the SUR1-C717S/Kir6.2 channel compared with the wild-type SUR1/Kir6.2 channel (n = 8, p < 0.02 vs. wild type; Figure 9C).
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ABCC8 p.Cys717Ser 19284878:196:66
status: NEW
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198 In addition to C717S, we further examined the activating effects of NO after mutating the cysteine residues within NBD1 and NBD2 to serine, including those cysteine residues adjacent to C717 within NBD1 (C806S), and all three cysteine residues within NBD2 (C1378, C1446, C1491).
X
ABCC8 p.Cys717Ser 19284878:198:15
status: NEW
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200 Among these mutants, only SUR1-C717S/Kir6.2 channels significantly affected NO-sensitivity compared with wild type SUR1/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:200:31
status: NEW
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216 of 20 (page number not for citation purposes) Figure 9 (see legend on next page) A B SUR1-C717/Kir6.2 Wild type SUR1/Kir6.2 SUR1-C717S/Kir6.2 Relative channel activity ATP 1 bc;M ATP 1 mM 5 pA 200 ms [ATP]i (bc;M) C SNAP ATP 1 mM SNAP + DTT ATP 1 mM (ATP 1 mM) SNAP (+) Relative channel activity wt SUR1 SUR1-C717S SUR1-C806S SUR1-C1378S SUR1-C1446S SUR1-C1491S wt SUR1 SUR1-C717S SUR1-C806S SUR1-C1378S SUR1-C1446S SUR1-C1491S control D SUR1-C717/Kir6.2 5 pA 200 ms * of 20 (page number not for citation purposes) Although the sGC/cGMP/PKG pathway mediates NO regulation of KATP channels in cardiomyocytes, vascular and non-vascular smooth muscle cells, and pancreatic b2; cells [52-56], this is not the case in DRG neurons.
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ABCC8 p.Cys717Ser 19284878:216:129
status: NEW
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ABCC8 p.Cys717Ser 19284878:216:315
status: NEW
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ABCC8 p.Cys717Ser 19284878:216:381
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239 (A) Representative traces of currents via SUR1-C717S/Kir6.2 channels in inside-out patches at -60 mV holding potential.
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ABCC8 p.Cys717Ser 19284878:239:47
status: NEW
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241 Arrows indicate closed channel state. (B) Concentration-response relationship curves between [ATP]i and relative NPo values for wild-type SUR1/Kir6.2 or SUR1-C717S/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:241:158
status: NEW
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244 (C) Representative current traces of SUR1-C717S/ Kir6.2 channel currents in inside-out patches at -60 mV holding potential. In the presence of 1 mM [ATP]i, bath application of SNAP (1 mM) activated SUR1-C717S/Kir6.2 channel, but less than wild-type SUR1/Kir6.2 channels.
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ABCC8 p.Cys717Ser 19284878:244:42
status: NEW
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ABCC8 p.Cys717Ser 19284878:244:203
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305 Point mutation of cysteine at position 717 (C717), C806, C1378, C1446, and C1491 within SUR1 to serine (C717S, C806S, C1378S, C1446S, and C1491S) was performed by using the Site-Directed Mutagenesis system (Invitrogen Corp.).
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ABCC8 p.Cys717Ser 19284878:305:104
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PMID: 10570926 [PubMed] Matsuo M et al: "NEM modification prevents high-affinity ATP binding to the first nucleotide binding fold of the sulphonylurea receptor, SUR1."
No. Sentence Comment
3 However, when the cysteine residue in the Walker A motif of the first nucleotide binding fold (NBF1) of SUR1 was replaced with serine (C717S), photoaffinity labeling was not inhibited by 100 WWM NEM. These results suggest that NBF1 of SUR1 has a NEM-sensitive structure similar to that of NBF1 of MDR1, a multidrug transporter, and confirm NBF1 as the high-affinity ATP binding site on SUR1.
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ABCC8 p.Cys717Ser 10570926:3:135
status: NEW
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27 The C717S and K1385M mutations used in this study were made in rat SUR1.
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ABCC8 p.Cys717Ser 10570926:27:4
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58 We therefore examined the e¡ects of NEM on 8-azido-ATP binding to a mutant form of SUR1, in which the cysteine residue within the Walker A motif of NBF1 was replaced with serine (C717S).
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ABCC8 p.Cys717Ser 10570926:58:183
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59 Membranes containing equal amounts of the wild-type and the C717S mutant form of SUR1 were treated with 100 WM NEM, and photoa¤nity labeling with 5 WM 8-azido-[Q-32 P]- ATP was then examined (Fig. 3).
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ABCC8 p.Cys717Ser 10570926:59:60
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60 Both wild-type and C717S SUR1 were photoa¤nity labeled to the same extent in the absence of NEM.
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ABCC8 p.Cys717Ser 10570926:60:19
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61 However, by contrast to wild-type SUR1, photoa¤nity labeling of C717S SUR1 was una¡ected by pretreatment with NEM.
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ABCC8 p.Cys717Ser 10570926:61:68
status: NEW
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73 The cysteine residue within the Walker A motif of NBF of SUR1 was replaced with serine in the C717S mutant form.
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ABCC8 p.Cys717Ser 10570926:73:94
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77 The inhibition of this high-a¤nity 8-azido-ATP binding to SUR1 by NEM and the lack of inhibition found with the C717S mutation now con'rms that NBF1 is the high-a¤nity ATP binding site identi'ed on SUR1.
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ABCC8 p.Cys717Ser 10570926:77:116
status: NEW
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