High impact information on Kcnk1

• TWIK-1, TREK-1 and TASK K+ channels comprise a class of pore-forming subunits with four membrane-spanning segments and two P domains [1].
• The two-pore domain K(+) channel, TRESK (TWIK-related spinal cord K(+) channel) is activated in response to the calcium signal by the calcium/calmodulin-dependent protein phosphatase, calcineurin [2].
• TWIK1 belongs to a family of K(+) channels involved in neuronal excitability and cell volume regulation [3].
• Of these, TWIK-1 and TASK-1 were preferentially expressed in taste cells relative to surrounding nonsensory epithelium [4].
• The twik gene (or KCNK1) has been mapped to chromosome 8, consistent with its localization to 1q42-43 in human [5].

Biological context of Kcnk1

• Its amino acid sequence shares 25% identity with mouse TWIK-1, 22% with mouse TREK-1, and 33% with a putative K+ channel of Caenorhabditis elegans (C40C9) [6].
• Structure, chromosome localization, and tissue distribution of the mouse twik K+ channel gene [5].
• The level of expression is increased in brain and kidney from neonate to adult animals, but the TWIK message is also detected during embryogenesis, as early as day 7 post conception [5].

Anatomical context of Kcnk1

• TWIK-1 mRNA is expressed abundantly in brain and at lower levels in lung, kidney, and skeletal muscle [7].
• We examined their expression in mouse vallate and foliate taste buds using RT-PCR, and detected TWIK-1 and -2, TREK-1 and -2, and TASK-1 [4].
• However, the evidence for TWIK-related acid-sensitive potassium (TASK)-like conductances in inhibitory interneurons is less clear, and mRNA expression has suggested that TASK channels are expressed in only a subpopulation of interneurons [8].

Associations of Kcnk1 with chemical compounds

• Acute pharmacologic blockade of the vasopressin V(2)-receptor revealed both an attenuated diuretic response and an attenuated internalization of aquaporin-2 in the inner medullary collecting duct in twik-1 -/- versus +/+ mice [9].

Other interactions of Kcnk1

• Western blot analysis and immunohistochemistry for the electrogenic 3Na(+)-1HPO(4) (2-)-cotransporter NaPi-2a revealed a reduced reno-cortical expression in twik-1 -/- mice under these conditions [9].

References