Kelch protein

Kelch proteins (and Kelch-like proteins) are a widespread group of proteins that contain multiple Kelch motifs. The kelch domain generally occurs as a set of five to seven kelch tandem repeats that form a β-propeller tertiary structure. Kelch-repeat β-propellers are generally involved in protein–protein interactions, though the large diversity of domain architectures and limited sequence identity between kelch motifs make characterisation of the kelch superfamily difficult.
Structure.
The N-terminus of several Kelch proteins contain other protein domains, including Discoidin, F-box, and Broad-complex, Tramtrack, Bric-a-Brac/Poxvirus Zinc finger (BTB/POZ) domains. Kelch proteins may also only have a β-propeller architecture. The BTB domain of kelch proteins (if present) allows the formation of homo- or heterodimers that mediate protein–protein interactions.
The C-terminus of Kelch proteins contains kelch repeats. Each kelch repeat is a sequence of 44–55 amino acids in length, usually occurring in clusters of 4 – 7 repeats.
Each kelch repeat forms a "blade" of the β-propeller fold, consisting of a four-stranded antiparallel β-sheet secondary structure, arranged radially around a central axis, packed onto its adjoining repeats via hydrophobic contacts.
Kelch-repeat β-propellers undergo a variety of binding interactions with other proteins, notably the actin filaments of a cell.
Function.
Kelch like proteins are known to act as substrate adaptors for Cullin 3 ubiquitin ligases.
Organisms.
The first Kelch protein (from which this family derives its name) was isolated from "Drosophila", in which Kelch-mutant females lay sterile, cup-shaped eggs; "Kelch" is German for "chalice", or "cup". Kelch proteins have also been isolated in many other animals, plants, bacteria, fungi, and even virus (restricted to Poxviridae).
Human proteins containing Kelch motifs.
ATRN; ATRNL1; CCIN; ENC1; FBXO42;
GAN; HCFC1; HCFC2; IPP; IVNS1ABP; KBTBD10; KBTBD11; KBTBD2;
KBTBD3; KBTBD4; KBTBD5; KBTBD6; KBTBD7; KBTBD8; KEAP1; 
KIAA1900; KLHDC1; KLHDC2; KLHDC3; KLHDC4; KLHDC5; KLHDC6; KLHDC7A; KLHDC7B;
KLHDC8A; KLHDC8B; KLHDC9; KLHDC10; KLHL1; KLHL10; KLHL11; KLHL12; KLHL13;
KLHL14; KLHL15; KLHL17; KLHL18; KLHL2; KLHL20; KLHL21; KLHL22;
KLHL23; KLHL24; KLHL25; KLHL26; KLHL28; KLHL29; KLHL3; KLHL30;
KLHL31; KLHL32; KLHL34; KLHL4; KLHL40; KLHL5; KLHL6; KLHL7; KLHL8;
KLHL9; LZTR1; MEGF8; MKLN1; RABEPK; SARCOSIN;