BTB (Broad-Complex, Tramtrack and Bric a brac)/POZ (poxvirus and zinc finger) domain found in potassium channel tetramerization domain-containing protein 5 (KCTD5)
KCTD5 is a BTB/POZ domain-containing protein that functions as a substrate adaptor for cullin3 based ubiquitin E3 ligases. It is a negative regulator of the AKT pathway, a key signaling cascade frequently deregulated in cancer. KCTD5 does not impact the operation of Kv4.2, Kv3.4, Kv2.1, or Kv1.2 channels. The BTB/POZ domain, also known as tetramerization (T1) domain, is a versatile protein-protein interaction motif that facilitates homodimerization or heterodimerization. KCTD family BTB domains can adopt a wide range of oligomerization geometries, including homodimerization, tetramerization, and pentamerization. KCTD5 forms pentamers mediated by its BTB domain.
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