- Shaker gene
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Shaker Identifiers Organism Symbol Sh Entrez 32780 RefSeq (mRNA) NM_167596 UniProt P08510 Other data Chromosome X: 17.8 - 17.98 Mb potassium voltage-gated channel, shaker-related subfamily, member 3 Identifiers Symbol KCNA3 Entrez 3738 HUGO 6221 OMIM 176263 RefSeq NM_002232 UniProt P22001 Other data Locus Chr. 1 p13.3 The shaker (Sh) gene, when mutated, causes a variety of atypical behaviors in the fruit fly, Drosophila melanogaster.[1][2][3][4] Under ether anesthesia, the fly’s legs will shake (hence the name); even when the fly is unanaesthetized, it will exhibit aberrant movements. Sh-mutant flies have a shorter lifespan than regular flies; in their larvae, the repetitive firing of action potentials as well as prolonged exposure to neurotransmitters at neuromuscular junctions occurs.
The Sh gene plays a part in the operation of potassium ion channels, which are integral membrane proteins and are essential to the correct functioning of the cell. A working Shaker channel is voltage-dependent and has four subunits which form a pore through which ions flow, carrying type-A potassium current (IA). A mutation in the Sh gene reduces the conductance of charge across the neuron since the channels do not work, causing the severe phenotypical aberrations mentioned above. These types of ion channels are responsible for the repolarization of the cell.
In Drosophila, It is located on the X chromosome. The closest human homolog is KCNA3.[5]
Recently, the Shaker gene has also been identified as a gene that helps determine an organism's amount of sleep. The phenotype of the flies that need less sleep is called minisleep (mns).[6]
References
- ^ Salkoff L, Wyman R (1981). "Genetic modification of potassium channels in Drosophila Shaker mutants". Nature 293 (5829): 228–30. doi:10.1038/293228a0. PMID 6268986.
- ^ Tempel BL, Papazian DM, Schwarz TL, Jan YN, Jan LY (August 1987). "Sequence of a probable potassium channel component encoded at Shaker locus of Drosophila". Science 237 (4816): 770–5. doi:10.1126/science.2441471. PMID 2441471.
- ^ Schwarz TL, Tempel BL, Papazian DM, Jan YN, Jan LY (January 1988). "Multiple potassium-channel components are produced by alternative splicing at the Shaker locus in Drosophila". Nature 331 (6152): 137–42. doi:10.1038/331137a0. PMID 2448635.
- ^ Lichtinghagen R, Stocker M, Wittka R, Boheim G, Stühmer W, Ferrus A, Pongs O (December 1990). "Molecular basis of altered excitability in Shaker mutants of Drosophila melanogaster". EMBO J. 9 (13): 4399–407. PMC 552231. PMID 1702382. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=552231.
- ^ HomoloGene: 20513
- ^ Cirelli C, Bushey D, Hill S, Huber R, Kreber R, Ganetzky B, Tononi G (April 2005). "Reduced sleep in Drosophila Shaker mutants". Nature 434 (7037): 1087–92. doi:10.1038/nature03486. PMID 15858564.
Ca2+: Calcium channel Ligand-gatedNa+: Sodium channel Constitutively activeProton gatedK+: Potassium channel Kvα1-6 (1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8) · (2.1, 2.2) · (3.1, 3.2, 3.3, 3.4) · (4.1, 4.2, 4.3) · (5.1) · (6.1, 6.2, 6.3, 6.4)
Kvα7-12 (7.1, 7.2, 7.3, 7.4, 7.5) · (8.1, 8.2) · (9.1, 9.2, 9.3) · (10.1, 10.2) · (11.1/hERG, 11.2, 11.3) · (12.1, 12.2, 12.3)
Kvβ (1, 2, 3) · KCNIP (1, 2, 3, 4) · minK/ISK · minK/ISK-like · MiRP (1, 2, 3) · Shaker geneOther Cl-: Chloride channelHVCN1GeneralCategories:- Genes on chromosome 1
- Genetics stubs
- Drosophilidae
- Genetic disorders
- Ion channels
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