InterPro domain: IPR033646

Mutations in the mitochondrial CLU proteins have been shown to result in clustered mitochondria [ 1 , 2 , 3 ]. CLU proteins include Saccharomyces cerevisiae clustered mitochondria protein (Clu1p, alias translation initiation factor 31/TIF31p), Dictyostelium discoideum clustered mitochondria protein homologue (CluA), Caenorhabditis elegans clustered mitochondria protein homologue (CLUH/ Protein KIAA0664), Drosophila clueless (alias clustered mitochondria protein homologue), Arabidopsis clustered mitochondria protein (CLU, alias friendly mitochondria protein/FMT), and human clustered mitochondria protein homologue (CLUH).

Dictyostelium CluA is involved in mitochondrial dynamics and is necessary for both, mitochondrial fission and fusion [ 4 ]. Drosophila clueless is essential for cytoplasmic localization and function of cellular mitochondria [ 5 ]. The Drosophila clu gene interacts genetically with parkin (park, the Drosophila ortholog of a human gene responsible for many familial cases of Parkinson's disease) [ 6 ]. Arabidopsis CLU/FMT is required for correct mitochondrial distribution and morphology [ 7 ]. The specific role CLU proteins play in mitochondrial processes in not yet known. In an early study, S. cerevisiae Clu1/TIF31p was reported as sometimes being associated with the elF3 translation initiation factor. The authors noted, however, that its tentative assignment as a subunit of elf3 was uncertain, and to date there has been no direct evidence for a role of this protein in translation [ 8 ].

This entry represents a central domain in CLU proteins.

1. Mitochondrial membrane dynamics are altered in cluA- mutants of Dictyostelium. J. Muscle Res. Cell. Motil. 23, 829-38
2. The cluA- mutant of Dictyostelium identifies a novel class of proteins required for dispersion of mitochondria. Proc. Natl. Acad. Sci. U.S.A. 94, 7308-13
3. The S. cerevisiae CLU1 and D. discoideum cluA genes are functional homologues that influence mitochondrial morphology and distribution. J. Cell. Sci. 111 ( Pt 12), 1717-27
4. Mitochondrial fission and fusion in Dictyostelium discoideum: a search for proteins involved in membrane dynamics. BMC Res Notes 5, 505
5. Drosophila clueless is highly expressed in larval neuroblasts, affects mitochondrial localization and suppresses mitochondrial oxidative damage. PLoS ONE 8, e54283
6. Clueless, a conserved Drosophila gene required for mitochondrial subcellular localization, interacts genetically with parkin. Dis Model Mech 2, 490-9
7. The genetic control of plant mitochondrial morphology and dynamics. Plant J. 36, 500-9
8. A 110-kilodalton subunit of translation initiation factor eIF3 and an associated 135-kilodalton protein are encoded by the Saccharomyces cerevisiae TIF32 and TIF31 genes. J. Biol. Chem. 274, 16802-12