Potassium voltage-gated channel, Shab-related subfamily, member 1, also known as KCNB1 or K_v2.1, is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 which in humans is encoded by the KCNB1 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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Species and tissue distribution

K_v2.1 channels are widely expressed in various tissues in mammals, including humans. They are found in cardiomyocytes, skeletal muscles, vascular smooth muscles, placental vasculature, retina, and pancreatic β-cells

Beta cell

Beta cells are a type of cell in the pancreas located in the so-called islets of Langerhans. They make up 65-80% of the cells in the islets.-Function:...

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Function

Voltage-gated potassium (K_v

Voltage-gated potassium channel

Voltage-gated potassium channels are transmembrane channels specific for potassium and sensitive to voltage changes in the cell's membrane potential. During action potentials, they play a crucial role in returning the depolarized cell to a resting state....

) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter

Neurotransmitter

Neurotransmitters are endogenous chemicals that transmit signals from a neuron to a target cell across a synapse. Neurotransmitters are packaged into synaptic vesicles clustered beneath the membrane on the presynaptic side of a synapse, and are released into the synaptic cleft, where they bind to...

 release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. Four sequence-related potassium channel genes - shaker

Shaker gene

The shaker gene, when mutated, causes a variety of atypical behaviors in the fruit fly, Drosophila melanogaster. Under ether anesthesia, the fly’s legs will shake ; even when the fly is unanaesthetized, it will exhibit aberrant movements...

, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shab-related subfamily. This member is a delayed rectifier potassium channel and its activity is modulated by some other family members.

In mouse cardiomyocytes, K_v2.1 channel is the molecular substrate of major repolarization current I_K-slow2. Transgenic

Genetically modified organism

A genetically modified organism or genetically engineered organism is an organism whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one...

 mice, expressing a dominant-negative isoform of K_v2.1, exhibit markedly prolonged action potential

Action potential

In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and...

s and demonstrate arrhythmia. In mammalian CNS neurons, K_v2.1 is a predominant delayed rectifier K⁺ current that regulates neuronal excitability, action potential duration, and tonic spiking. In Drosophila

Drosophila

Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" or more appropriately pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit...

 photoreceptor cells, the K_v2 channel is the key component of light-induced membrane voltage response. Genetic abolition of this current dramatically decreases photoreceptor information capacity.

Interactions

KCNB1 has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with PTPRE

PTPRE

Receptor-type tyrosine-protein phosphatase epsilon is an enzyme that in humans is encoded by the PTPRE gene.-Further reading:...

 and KCNH1

KCNH1

Potassium voltage-gated channel subfamily H member 1 is a protein that in humans is encoded by the KCNH1 gene.- External links :...

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