K+ voltage-gated channel subfamily D member 2; voltage-gated K+ channel subunit Kv4.2 (KCND2, KIAA1044)

Function

• pore-forming (alpha) subunit of voltage-gated rapidly inactivating A-type K+ channels
• may contribute to I(To) current in heart & I(Sa) current in neurons
• channel properties are modulated by interactions with other alpha subunits & with regulatory subunits
• phosphorylated on Ser & Thr
• homotetramer or heterotetramer with KCND1 &/or KCND3
• interacts with DPP6, DLG4 & NCS1/FREQ (putative)
• interacts with DLG1
• associates with the regulatory subunits KCNIP1, KCNIP2, KCNIP3 & KCNIP4
• probably part of a complex consisting of KCNIP1, KCNIP2 isoform 3 & KCND2
• the KCND2-KCNIP2 channel complex contains 4 KCND2 & 4 KCNIP2 subunits
• interacts with FLNA, FLNC & DPP10

Structure

• the segment S4 is probably the voltage-sensor & is characterized by a series of positively charged amino acids at every third position
• belongs to the K+ channel family, D (Shal) (TC 1.A.1.2) subfamily, Kv4.2/KCND2 sub-subfamily

Compartment

• cell membrane; multi-pass membrane protein
• cell projection, dendrite
• detected in dendrites in cultured hippocampal neurons
• association with KCNIP2 probably enhances cell surface expression

Expression

• highly expressed throughout the brain
• expression is very low or absent in other tissues

More general terms

• transmembrane 6 protein
• K+ channel subfamily D
• glycoprotein
• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=3751
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:3751
• OMIM: https://mirror.omim.org/entry/605410
• UniProt: http://www.uniprot.org/uniprot/Q9NZV8.html