Summary: KCNMB2, ball and chain domain
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KCNMB2 Edit Wikipedia article
|, potassium calcium-activated channel subfamily M regulatory beta subunit 2|
|KCNMB2, ball and chain domain|
solution structure of the cytoplasmic n-terminus of the bk beta-subunit kcnmb2
MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can contain two distinct subunits: a pore-forming alpha subunit and a modulatory beta subunit. Each complete MaxiK channel contains four copies of the pore-forming alpha subunit and up to four beta subunits. The protein encoded by the KCNMB2 gene is an auxiliary beta subunit which influences the calcium sensitivity of MaxiK currents and, following activation of MaxiK current, causes persistent inactivation. The subunit encoded by the KCNMB2 gene is expressed in various endocrine cells, including pancreas and adrenal chromaffin cells. It is also found in the brain, including the hippocampus. The KCNMB2 gene is homologous to three other genes found in mammalian genomes: KCNMB1 (found primarily in smooth muscle), KCNMB3, and KCNMB4 (the primary brain MaxiK auxiliary subunit).
Calcium-activated potassium channel subunit beta-2 comprises two domains. An N-terminal cytoplasmic domain, the ball and chain domain, which is responsible for the fast inactivation of these channels, and a C-terminal calcium-activated potassium channel beta subunit domain. The N-terminal domain only occurs in calcium-activated potassium channel subunit beta-2, while the C-terminal domain is found in related proteins.
- GRCh38: Ensembl release 89: ENSG00000197584 - Ensembl, May 2017
- GRCm38: Ensembl release 89: ENSMUSG00000037610 - Ensembl, May 2017
- "Human PubMed Reference:".
- "Mouse PubMed Reference:".
- Wallner M, Meera P, Toro L (May 1999). "Molecular basis of fast inactivation in voltage and Ca2+-activated K+ channels: a transmembrane beta-subunit homolog". Proc Natl Acad Sci U S A. 96 (7): 4137–42. PMC . PMID 10097176. doi:10.1073/pnas.96.7.4137.
- "Entrez Gene: KCNMB2 potassium large conductance calcium-activated channel, subfamily M, beta member 2".
- Bentrop D, Beyermann M, Wissmann R, Fakler B (November 2001). "NMR structure of the "ball-and-chain" domain of KCNMB2, the beta 2-subunit of large conductance Ca2+- and voltage-activated potassium channels". J. Biol. Chem. 276 (45): 42116–21. PMID 11517232. doi:10.1074/jbc.M107118200.
- Orio P, Rojas P, Ferreira G, Latorre R (2002). "New disguises for an old channel: MaxiK channel beta-subunits". News Physiol. Sci. 17: 156–61. PMID 12136044. doi:10.1152/nips.01387.2002.
- Xia XM, Ding JP, Lingle CJ (1999). "Molecular basis for the inactivation of Ca2+- and voltage-dependent BK channels in adrenal chromaffin cells and rat insulinoma tumor cells". J. Neurosci. 19 (13): 5255–64. PMID 10377337.
- Brenner R, Jegla TJ, Wickenden A, et al. (2000). "Cloning and functional characterization of novel large conductance calcium-activated potassium channel beta subunits, hKCNMB3 and hKCNMB4". J. Biol. Chem. 275 (9): 6453–61. PMID 10692449. doi:10.1074/jbc.275.9.6453.
- Liu QH, Williams DA, McManus C, et al. (2000). "HIV-1 gp120 and chemokines activate ion channels in primary macrophages through CCR5 and CXCR4 stimulation". Proc. Natl. Acad. Sci. U.S.A. 97 (9): 4832–7. PMC . PMID 10758170. doi:10.1073/pnas.090521697.
- Uebele VN, Lagrutta A, Wade T, et al. (2000). "Cloning and functional expression of two families of beta-subunits of the large conductance calcium-activated K+ channel". J. Biol. Chem. 275 (30): 23211–8. PMID 10766764. doi:10.1074/jbc.M910187199.
- Meera P, Wallner M, Toro L (2000). "A neuronal beta subunit (KCNMB4) makes the large conductance, voltage- and Ca2+-activated K+ channel resistant to charybdotoxin and iberiotoxin". Proc. Natl. Acad. Sci. U.S.A. 97 (10): 5562–7. PMC . PMID 10792058. doi:10.1073/pnas.100118597.
- Bentrop D, Beyermann M, Wissmann R, Fakler B (2001). "NMR structure of the "ball-and-chain" domain of KCNMB2, the beta 2-subunit of large conductance Ca2+- and voltage-activated potassium channels". J. Biol. Chem. 276 (45): 42116–21. PMID 11517232. doi:10.1074/jbc.M107118200.
- Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. PMC . PMID 12477932. doi:10.1073/pnas.242603899.
- Xia XM, Ding JP, Lingle CJ (2003). "Inactivation of BK channels by the NH2 terminus of the beta2 auxiliary subunit: an essential role of a terminal peptide segment of three hydrophobic residues". J. Gen. Physiol. 121 (2): 125–48. PMC . PMID 12566540. doi:10.1085/jgp.20028667.
- Hartness ME, Brazier SP, Peers C, et al. (2004). "Post-transcriptional control of human maxiK potassium channel activity and acute oxygen sensitivity by chronic hypoxia". J. Biol. Chem. 278 (51): 51422–32. PMID 14522958. doi:10.1074/jbc.M309463200.
- Gerhard DS, Wagner L, Feingold EA, et al. (2004). "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. PMC . PMID 15489334. doi:10.1101/gr.2596504.
- Orio P, Torres Y, Rojas P, et al. (2006). "Structural determinants for functional coupling between the beta and alpha subunits in the Ca2+-activated K+ (BK) channel". J. Gen. Physiol. 127 (2): 191–204. PMC . PMID 16446507. doi:10.1085/jgp.200509370.
- Zeng XH, Benzinger GR, Xia XM, Lingle CJ (2007). "BK channels with beta3a subunits generate use-dependent slow afterhyperpolarizing currents by an inactivation-coupled mechanism". J. Neurosci. 27 (17): 4707–15. PMID 17460083. doi:10.1523/JNEUROSCI.0758-07.2007.
- Zarei MM, Song M, Wilson RJ, et al. (2007). "Endocytic trafficking signals in KCNMB2 regulate surface expression of a large conductance voltage and Ca(2+)-activated K+ channel". Neuroscience. 147 (1): 80–9. PMID 17521822. doi:10.1016/j.neuroscience.2007.04.019.
- KCNMB2 human gene location in the UCSC Genome Browser.
- KCNMB2 human gene details in the UCSC Genome Browser.
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KCNMB2, ball and chain domain Provide feedback
Members of this family are found in the cytoplasmic N-terminus of KCNMB2, the beta-2 subunit of large conductance calcium and voltage-activated potassium channels. They are responsible for the fast inactivation of these channels .
Bentrop D, Beyermann M, Wissmann R, Fakler B; , J Biol Chem. 2001;276:42116-42121.: NMR structure of the "ball-and-chain" domain of KCNMB2, the beta 2-subunit of large conductance Ca2+- and voltage-activated potassium channels. PUBMED:11517232 EPMC:11517232
This tab holds annotation information from the InterPro database.
InterPro entry IPR015382
This domain is found in the cytoplasmic N terminus of KCNMB2, the beta-2 subunit of large conductance calcium and voltage-activated potassium channels. It is responsible for the fast inactivation of these channels [PUBMED:11517232].
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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|Author:||Mistry J , Sammut SJ|
|Number in seed:||6|
|Number in full:||146|
|Average length of the domain:||27.00 aa|
|Average identity of full alignment:||77 %|
|Average coverage of the sequence by the domain:||11.74 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 45638612 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||10|
|Download:||download the raw HMM for this family|
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Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
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The tree shows the occurrence of this domain across different species. More...
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
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There is 1 interaction for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the KcnmB2_inactiv domain has been found. There are 1 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.
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