The CLU domain (CLUstered mitochondria) is a eukaryotic domain found in proteins from fungi, protozoa, plants to humans. It is required for correct functioning of the mitochondria and mitochondrial transport [1,2] although the exact function of the domain is unknown [4]. In Dictyostelium the full-length protein is required for a very late step in fission of the outer mitochondrial membrane [2] suggesting that mitochondria are transported along microtubules, as in mammalian cells, rather than along actin filaments, as in budding yeast [1]. Disruption of the protein-impaired cytokinesis and caused mitochondria to cluster at the cell centre [1]. It is likely that CLU functions in a novel pathway that positions mitochondria within the cell based on their physiological state. Disruption of the CLU pathway may enhance oxidative damage, alter gene expression, cause mitochondria to cluster at microtubule plus ends, and lead eventually to mitochondrial failure [3].

1: The cluA- mutant of Dictyostelium identifies a novel class of proteins required for dispersion of mitochondria. Zhu Q, Hulen D, Liu T, Clarke M; Proc Natl Acad Sci U S A. 1997;94:7308-7313. PMID:9207087

2: Mitochondrial membrane dynamics are altered in cluA- mutants of Dictyostelium. Fields SD, Arana Q, Heuser J, Clarke M; J Muscle Res Cell Motil. 2002;23:829-838. PMID:12952081

3: Clueless, a conserved Drosophila gene required for mitochondrial subcellular localization, interacts genetically with parkin. Cox RT, Spradling AC; Dis Model Mech. 2009;2:490-499. PMID:19638420

4: Two novel Src homology 2 domain proteins interact to regulate dictyostelium gene expression during growth and early development. Sugden C, Ross S, Bloomfield G, Ivens A, Skelton J, Mueller-Taubenberger A, Williams JG; J Biol Chem. 2010;285:22927-22935. PMID:20457612