Kv channel-interacting protein 2; KChIP2; A-type K+ channel modulatory protein 2; K+ channel-interacting protein 2; cardiac voltage gated K+ channel modulatory subunit (KCNIP2, KCHIP2)

Function: 1) regulatory subunit of Kv4/D (Shal)-type voltage-gated rapidly inactivating A-type K⁺ channels 2) modulates channels density, inactivation kinetics & rate of recovery from inactivation 3) Ca⁺²-dependent 4) in vitro, modulates Kv4.2 & Kv4.3 currents 5) Kv4.2 & Kv4.3 trafficking to the cell surface 6) component of heteromultimeric K⁺ channels; Kv4.2/KCNIP2 channel complex contains 4 Kv4.2 & 4 KCNIP2 subunits 7) isoform 1 & isoform 3 interact with Kv4.3 isoform 1 8) involved in KCND2 & KCND3 trafficking to the cell surface 9) may be required for the expression of I(To) currents in the heart Structure: - at least isoform 2 & isoform 3 can self-associate to form homodimers & homotetramers - belongs to the recoverin family - contains 4 EF-hand domains Compartment: - cell membrane, lipid-anchor (palmitate) - palmitoylation enhances association with plasma membrane Alternative splicing: named isoforms=9 Expression: - expressed in brain - colocalizes with Kv4.2 in excitatory neurons including cortical & hippocampal CA1 pyramidal cells - isoform 3 is expressed in heart, umbilical vein endothelial cells - not expressed in fetal heart

General

Ca+2 binding protein membrane protein

Properties

SIZE: MW = 31 kD entity length = 270 aa COMPARTMENT: cellular membrane MOTIF: cysteine residue {C45} MODIFICATION: palmitate COMPARTMENT: membrane cysteine residue {C46} MODIFICATION: palmitate COMPARTMENT: membrane EF hand SITE: 81-137 EF hand SITE: 140-175 EF hand SITE: 176-211 EF hand SITE: 224-259 MOTIF: Ca+2-binding site SITE: 237-248 binding site SITE: 257-270 FOR-BINDING-OF: K+ voltage-gated channel subfamily D member 2

Database Correlations

OMIM 604661 UniProt Q9NS61 Pfam PF13499 Entrez Gene 30819 Kegg hsa:30819

References

UniProt :accession Q9NS61