Biochemical and Biophysical Research Communications
Regular ArticleImmunological and Physical Characterization of the Brain G Protein-Gated Muscarinic Potassium Channel
References (0)
Cited by (31)
Differential distribution and function of GABA<inf>B</inf>Rs in somato-dendritic and axonal compartments of principal cells and interneurons in cortical circuits
2018, NeuropharmacologyCitation Excerpt :Postsynaptic GABABRs activity is primarily mediated by G-protein-coupled inwardly rectifying K+ (Kir3) channels (Gähwiler and Brown, 1985; Andrade et al., 1986; Thompson and Gähwiler, 1992; Sodickson and Bean, 1996; Lüscher et al., 1997; Kaupmann et al., 1998b), which control neuronal excitability by producing slow inhibitory synaptic responses and contributing to the resting membrane potential (Chen and Johnston, 2005). Functional Kir3 channels exist as homotetrameric or heterotetrameric complexes formed upon co-assembly of the Kir3.1–3.4 subunits (Inanobe et al., 1995; Slesinger et al., 1996; Liao et al., 1996; Dascal, 1997). In the cortex, Kir3 channels are known to be mainly composed of the Kir3.1 and Kir3.2 subunits (Fig. 1F) (Lesage et al., 1995; Leaney, 2003) and the latter protein is responsible primarily for the assembly and surface localization of functional channels (Inanobe et al., 1999; Ma et al., 2002).
Structural Insights into GIRK Channel Function
2015, International Review of NeurobiologyCitation Excerpt :After identification of the cDNA clones for ROMK1 (Kir1.1) (Ho et al., 1993) and IRK1 (Kir2.1) (Kubo, Baldwin, Jan, & Jan, 1993), the GIRK1 (Kir3.1) cDNA was first isolated (Dascal et al., 1993; Kubo, Reuveny, Slesinger, Jan, & Jan, 1993), followed by the cloning of three additional GIRK subunits (GIRK2–GIRK4) (Kofuji, Davidson, & Lester, 1995; Krapivinsky, Gordon, et al., 1995; Lesage et al., 1994). Toxin-binding studies using chimeras, mutants, and concatemers, as well as protein biochemistry, demonstrated that GIRK channels (as well as other Kir channels) assemble into tetramers (Glowatzki et al., 1995; Inanobe, Ito, Ito, Hosoya, & Kurachi, 1995; MacKinnon, 1991; Tinker, Jan, & Jan, 1996; Yang, Jan, & Jan, 1995b). Using heterologous expression systems and biochemical measurements, the IKACh channel was determined to be a heterotetramer composed of GIRK1 and GIRK4 subunits (Krapivinsky, Gordon, et al., 1995), while brain GIRK channels were heterotetramers of GIRK1 and GIRK2, GIRK1 and GIRK3, or GIRK2 and GIRK3 (Jelacic, Kennedy, Wickman, & Clapham, 2000; Jelacic, Sims, & Clapham, 1999; Krapivinsky, Gordon, et al., 1995).
Membrane channels as integrators of G-protein-mediated signaling
2014, Biochimica et Biophysica Acta - BiomembranesCitation Excerpt :A growing number of microbial genome sequences indicate that prokaryotes occasionally possess genes encoding Kir channels [132]. Four individual subunits within the same subgroup of Kir channels assemble to form homo- or heteromeric units [129,130,133,134]. IKACh comprises of Kir3.1 and Kir3.4 [135,136].
Mapping the Gβγ-binding sites in GIRK1 and GIRK2 subunits of the G protein-activated K<sup>+</sup> channel
2003, Journal of Biological ChemistryStructural characterization of the mouse Girk genes
2002, GeneCitation Excerpt :GIRK subunits contain cytoplasmic amino- and carboxyl-termini, two membrane-spanning domains, and a hydrophobic pore sequence similar to other highly K+-selective channels. Evidence for homo- and heteromultimerization of GIRK subunits has come from heterologous expression experiments as well as cloning and biochemical studies in heart, brain, testis, and pancreas (Krapivinsky et al., 1995a; Ferrer et al., 1995; Lesage et al., 1995b; Inanobe et al., 1995; Kofuji et al., 1995; Wischmeyer et al., 1997; Inanobe et al., 1999b). Together, these findings suggest that GIRK subunits assemble according to unknown constraints to generate G protein-gated K+ channels with similar functional properties.