ABCC8 and ABCC9: ABC transporters that regulate K+ channels

@article{Bryan2006ABCC8AA,
  title={ABCC8 and ABCC9: ABC transporters that regulate K+ channels},
  author={Joseph Bryan and Alvaro Mu{\~n}oz and Xinna Zhang and Martina D{\"u}fer and Gisela Drews and Peter Krippeit-Drews and Lydia Aguilar-Bryan},
  journal={Pfl{\"u}gers Archiv - European Journal of Physiology},
  year={2006},
  volume={453},
  pages={703-718}
}
The sulfonylurea receptors (SURs) ABCC8/SUR1 and ABCC9/SUR2 are members of the C-branch of the transport adenosine triphosphatase superfamily. Unlike their brethren, the SURs have no identified transport function; instead, evolution has matched these molecules with K+ selective pores, either KIR6.1/KCNJ8 or KIR6.2/KCNJ11, to assemble adenosine triphosphate (ATP)-sensitive K+ channels found in endocrine cells, neurons, and both smooth and striated muscle. Adenine nucleotides, the major… Expand
The Sulfonylurea Receptor, an Atypical ATP-Binding Cassette Protein, and Its Regulation of the KATP Channel
TLDR
The structure and function of ABC proteins are reviewed and SUR, its regulation of the KATP channel, and its role in cardiovascular disease are discussed. Expand
Mechanism of pharmacochaperoning in KATP channels revealed by cryo-EM
TLDR
Comparing cryoEM structures of KATP channels bound to pharmacochaperones glibenclamide, repaglinide, and carbamazepine reveals a common mechanism by which diverse compounds stabilize the Kir6.2 N-terminus within the SUR1 ABC core, allowing it to act as a firm “handle” for the assembly of metastable mutant SUR1-Kir 6.2 complexes. Expand
Mechanism of pharmacochaperoning in a mammalian KATP channel revealed by cryo-EM
TLDR
Comparing cryoEM structures of a mammalian KATP channel bound to pharmacochaperones glibenclamide, repaglinide, and carbamazepine reveals a common mechanism by which diverse compounds stabilize the Kir6.2 N-terminus within SUR1’s ABC core, allowing it to act as a firm ‘handle’ for the assembly of metastable mutant SUR1-Kir 6.2 complexes. Expand
Studies of the ATPase activity of the ABC protein SUR1
TLDR
The data demonstrate that the ATPase activity of sulfonylurea receptor 1 differs from that of the isolated nucleotide‐binding domains, suggesting that the transmembrane domains may influence the activity of the protein. Expand
ATP binding without hydrolysis switches sulfonylurea receptor 1 (SUR1) to outward-facing conformations that activate KATP channels
TLDR
The results suggest that ATP binding to SUR1 biases KATP channels toward open states, consistent with SUR1 variants with lower KD values causing neonatal diabetes, whereas increased KD values cause congenital hyperinsulinism. Expand
1 Structure and mechanism of ATP-binding cassette exporters
The majority of proteins that belong to the ATP-binding cassette (ABC) superfamily are transporters that mediate the efflux of substrates from cells. These exporters include multidrug resistanceExpand
Sar1-GTPase-dependent ER exit of KATP channels revealed by a mutation causing congenital hyperinsulinism.
TLDR
It is concluded that surface expression of K(ATP) channels is critically dependent on the Sar1-GTPase-dependent ER exit mechanism and abrogation of the di-acidic ER exit signal leads to CHI. Expand
Human KATP channelopathies: diseases of metabolic homeostasis
  • T. Olson, A. Terzic
  • Biology, Medicine
  • Pflügers Archiv - European Journal of Physiology
  • 2009
TLDR
Advances in molecular medicine in the emerging field of human KATP channelopathies offer new opportunities for targeted individualized screening, early diagnosis, and tailored therapy. Expand
Interaction of asymmetric ABCC9-encoded nucleotide binding domains determines KATP channel SUR2A catalytic activity.
TLDR
NBD1/NBD2 assembly, resolved by a panel of proteomic approaches, provides a molecular substrate that determines the optimal catalytic activity in SUR2A, establishing a paradigm for the structure-function relationship within the K ATP channel complex. Expand
Regulation of hepatic ABCC transporters by xenobiotics and in disease states
TLDR
The regulation of hepatic ABCC transporters in humans and rodents by a variety of xenobiotics, under disease states and in genetically modified animal models deficient in transcription factors, transporter, and cell-signaling molecules is described. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 170 REFERENCES
SUR, ABC proteins targeted by KATP channel openers.
TLDR
Current knowledge on the molecular basis of the interaction of classical K(ATP) channel openers (cromakalim, pinacidil, diazoxide) with SUR is reviewed. Expand
Two Regions of Sulfonylurea Receptor Specify the Spontaneous Bursting and ATP Inhibition of KATP Channel Isoforms*
TLDR
This work has used matched chimeras of SUR1 and SUR2A to show that the kinetics, which determine the maximal open probability (Pomax), and the ATP sensitivity are functionally separable and to identify the two segments of SUR responsible for these isoform differences. Expand
Toward understanding the assembly and structure of KATP channels.
TLDR
The cloning and reconstitution of the subunits of these channels demonstrate they are heteromultimers of inwardly rectifying potassium channel subunits (KIR6.x) and sulfonylurea receptors (SUR), members of the ATP-binding cassette (ABC) superfamily. Expand
The tolbutamide site of SUR1 and a mechanism for its functional coupling to KATP channel closure
TLDR
The mechanism of inhibition of β‐cell KATP channels by sulfonylureas during treatment of non‐insulin‐dependent diabetes mellitus thus involves two components, drug‐binding and conformational changes within SUR1 which are coupled to the pore subunit through its N‐terminus and the disruption of nucleotide‐dependent stimulatory effects of the regulatory subunit on the pores. Expand
Truncation of Kir6.2 produces ATP-sensitive K+ channels in the absence of the sulphonylurea receptor
TLDR
It is shown that the primary site at which ATP acts to mediate K-ATP channel inhibition is located on Kir6.2, and that SUR1 is required for sensitivity to sulphonylureas and diazoxide and for activation by Mg-ADP. Expand
The molecular basis of the specificity of action of KATP channel openers
TLDR
This first glimpse of the site of action of pharmacological openers should permit rapid progress towards understanding the structural determinants of their affinity and specificity. Expand
KATP channels gated by intracellular nucleotides and phospholipids.
TLDR
The mechanisms and molecular determinants that underlie gating of KATP channel by nucleotides and phospholipids and their physiological implications are discussed. Expand
Octameric Stoichiometry of the KATP Channel Complex
ATP-sensitive potassium (KATP) channels link cellular metabolism to electrical activity in nerve, muscle, and endocrine tissues. They are formed as a functional complex of two unrelated subunits—aExpand
Molecular Basis for KATP Assembly Transmembrane Interactions Mediate Association of a K+ Channel with an ABC Transporter
TLDR
The identification of specific transmembrane interactions involved in K(ATP) assembly may provide a clue as to how ABC proteins that transport hydrophobic substrates evolved to regulate other membrane proteins. Expand
Insulin secretagogues, sulfonylurea receptors and K(ATP) channels.
TLDR
The extensive pharmacologic structure-activity-relationship data on these channels is integrated, which defines a bipartite drug binding pocket in the SUR (sulfonylurea receptor), with recent structure-function studies that identify domains of SUR and K(IR)6.2 neuroendocrine channels that are important for the regulation of insulin secretion. Expand
...
1
2
3
4
5
...