TABLE 33

KV9.3 channels

Channel name KV9.31,2,3
Description Modifier/silencer
Other names None
Molecular information Human: 491aa, NM_023966, NM_002252, chr. 2p24, KCNS3 (see `Comments'), GeneID: 3790, PMID: 93624761
Mouse: 491aa, NM_173417, chr. 12
Rat: 491aa, NM_031778, chr. 6q14
Associated subunits Coassembles with KV2 family channels
Functional assays Voltage-clamp
Current KV9.3/KV2.1 and ATP-dependent delayed rectifier channel in oxygen-sensitive pulmonary myocytes
Conductance Not functional on its own
Ion selectivity Not functional on its own
Activation Not functional on its own
Inactivation KV9.3/KV2.1 heteromers inactivate in a fast and complete fashion from intermediate closed states but in a slow and incomplete manner from open states4
Activators None
Gating inhibitors None
Blockers Hypoxia blocks KV9.3/KV2.1 channels5
Radioligands None
Channel distribution Brain, breast, colon, eye, lens, heart, kidney, muscle, lung, testis, skin, stomach, uterus6; also found in lens epithelium3
Physiological functions Regulation of membrane potential in pulmonary artery myocytes
Mutations and pathophysiology Not established
Pharmacological significance Pulmonary artery hypertension
Comments The human KV9.3 gene is intronless across the coding region 3′-UTR and all of the analysed 5′-UTR
  • aa, amino acids; chr., chromosome; UTR, untranslated region.

  • 1. Patel AJ, Lazdunski M, and Honore E (1997) Kv2.1/Kv9.3, a novel ATP-dependent delayed-rectifier K+ channel in oxygen-sensitive pulmonary artery myocytes. EMBO J 16:6615-6625

  • 2. Stocker M and Kerschensteiner D (1998) Cloning and tissue distribution of two new potassium channel α-subunits from rat brain. Biochem Biophys Res Commun 248:927-934

  • 3. Shepard AR and Raem JL (1999) Electrically silent potassium channel subunits from human lens epithelium. Am J Physiol 277, C412-C424

  • 4. Kerschensteiner D and Stocker M (1999) Heteromeric assembly of Kv2.1 with Kv9.3: effect on the state dependence of inactivation. Biophys J 77:248-257

  • 5. Hulme JT, Coppock EA, Felipe A, Martens JR, and Tamkun MM (1999) Oxygen sensitivity of cloned voltage-gated K+ channels expressed in the pulmonary vasculature. Circ Res 85:489-497

  • 6. UniGeneCluster Hs0.47584; OMIM no. 603888