Repeat

Kelch repeat type 2 (IPR011498)

Short name: Kelch_2

Description

Kelch is a 50-residue motif, named after the Drosophila mutant in which it was first identified [PMID: 8453663]. This sequence motif represents one beta-sheet blade, and several of these repeats can associate to form a beta-propeller. For instance, the motif appears 6 times in Drosophila egg-chamber regulatory protein, creating a 6-bladed beta-propeller. The motif is also found in mouse protein MIPP [PMID: 8453663] and in a number of poxviruses. In addition, kelch repeats have been recognised in alpha- and beta-scruin [PMID: 7593276, PMID: 7822422], and in galactose oxidase from the fungus Dactylium dendroides [PMID: 8126718, PMID: 2002850]. The structure of galactose oxidase reveals that the repeated sequence corresponds to a 4-stranded anti-parallel beta-sheet motif that forms the repeat unit in a super-barrel structural fold [PMID: 8182749].

The known functions of kelch-containing proteins are diverse: scruin is an actin cross-linking protein; galactose oxidase catalyses the oxidation of the hydroxyl group at the C6 position in D-galactose; neuraminidase hydrolyses sialic acid residues from glycoproteins; and kelch may have a cytoskeletal function, as it is localised to the actin-rich ring canals that connect the 15 nurse cells to the developing oocyte in Drosophila [PMID: 7593276]. Nevertheless, based on the location of the kelch pattern in the catalytic unit in galactose oxidase, functionally important residues have been predicted in glyoxal oxidase [PMID: 8126718].

This entry represents a type of kelch sequence motif that comprises one beta-sheet blade.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005515 protein binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam