KLHL1 (kelch-like protein 1) is a 748 amino acid protein that is the homolog of the Drosophila kelch protein. Localized to the cytoskeleton, KLHL1 contains six kelch repeats and one BTB (POZ) domain. The BTB (Broad-Complex, Tramtrack and Bric a brac) domain, also known as the POZ (Poxvirus and Zinc finger) domain, is an N-terminal homodimerization domain that contains multiple copies of kelch repeats and/or C2H2-type zinc fingers.