Kvβ2
Description: potassium voltage-gated channel, shaker-related subfamily, beta member 2 Gene: kcnab2 Alias: kcnab2, KvBeta2
This entry is about a potassium voltage-gated channel, shaker-related subfamily, beta member 2, also known as F5; I2rf5; Kcnb3.
Gene
Transcript
| Species | NCBI accession | Length (nt) | |
|---|---|---|---|
| Human | NM_003636.4 | 3875 | |
| Mouse | NM_001252656.2 | 3645 | |
| Rat | NM_017304.2 | 1590 |
Protein Isoforms
Isoforms
Post-Translational Modifications
It is not known whether the C termini of Kv channels assume a well defined 3D structure, but there is an increasing number of examples of the C-terminal domain of K+ channels assuming highly ordered structures, which play a fundamental role in channel function [625], [626]. Furthermore, Ju et al. [5] have proposed that the gating of the Kv2.1 channel is strongly influenced by specific interactions between the N- and C- terminal domains, suggesting they do assume a well defined 3D structure.
Auxiliary beta subunits bind to the alpha-subunit tetramer to form a heterooctameric complex [627], [628]. The binding occurs through the interaction of the Kv-beta C terminus with conserved loops in the Kv-alpha subunit N-terminal T1 domain [620].
Discussion of 3D structure of Shaker can be found in [304].
Kvβ2 predicted AlphaFold size
Methodology for AlphaFold size prediction and disclaimer are available here
Kvb expression is restricted to the spinal cord and dorsal root ganglia in the embryonic rat CNS. At birth, Kvb expression is detected in brainstem and midbrain nuclei, but not detected in the hippocampus, cerebellum or cerebral cortex. During the first postnatal week, Kvb expression is present in hippocampal and cortical pyramidal cells and in cerebellar Purkinje cells. Expression of Kvb subunits reaches adult levels by the third postnatal week in all of the brain regions examined. A rabbit antiserum directed against a unique peptide sequence in the N-terminus of the Kvb1 protein demonstrates that this subunit displays a novel expression pattern in the developing mouse brain. Kvb1 expression is high at birth in all brain regions examined and decreases with age. In contrast, Kvb2 expression is low at birth and increases with age to reach adult levels by the third postnatal week. [310]
It is known that in Shaker-like K+ channels, C termini are involved in a variety of processes that range from channel gating [621] [622] and voltage sensitivity [615] to the binding of the membrane-associated guanylate kinases [623]. They also participate in channel assembly in Kv 2.1 [624].
Kv-beta is known to modulate both the biosynthesis and the function of Kv channels. Coexpression of Kv-beta with Kv-alpha enhances channel synthesis and cell surface targeting [629], [630], [631].
Kvb2 (Kv-beta-2) accelerates a C-type inactivation of Kv1.4 channels [632] and the activation of Kv1.5 channels, and that it alters the activation threshold of Kv1.1 and Kv1.5 channels [633]. In vivo, Kvb2 can also indirectly modulate Kv channel inactivation by competing with other Kvb (Kvb1 or -3) for Kv-alpha-binding sites [634].
References
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Contributors: Rajnish Ranjan, Michael Schartner
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