Genetic modifiers of abnormal organelle biogenesis in a Drosophila model of BLOC-1 deficiency.

Autor: Cheli VT; Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA., Daniels RW, Godoy R, Hoyle DJ, Kandachar V, Starcevic M, Martinez-Agosto JA, Poole S, DiAntonio A, Lloyd VK, Chang HC, Krantz DE, Dell'Angelica EC
Jazyk: angličtina
Zdroj: Human molecular genetics [Hum Mol Genet] 2010 Mar 01; Vol. 19 (5), pp. 861-78. Date of Electronic Publication: 2009 Dec 16.
DOI: 10.1093/hmg/ddp555
Abstrakt: Biogenesis of lysosome-related organelles complex 1 (BLOC-1) is a protein complex formed by the products of eight distinct genes. Loss-of-function mutations in two of these genes, DTNBP1 and BLOC1S3, cause Hermansky-Pudlak syndrome, a human disorder characterized by defective biogenesis of lysosome-related organelles. In addition, haplotype variants within the same two genes have been postulated to increase the risk of developing schizophrenia. However, the molecular function of BLOC-1 remains unknown. Here, we have generated a fly model of BLOC-1 deficiency. Mutant flies lacking the conserved Blos1 subunit displayed eye pigmentation defects due to abnormal pigment granules, which are lysosome-related organelles, as well as abnormal glutamatergic transmission and behavior. Epistatic analyses revealed that BLOC-1 function in pigment granule biogenesis requires the activities of BLOC-2 and a putative Rab guanine-nucleotide-exchange factor named Claret. The eye pigmentation phenotype was modified by misexpression of proteins involved in intracellular protein trafficking; in particular, the phenotype was partially ameliorated by Rab11 and strongly enhanced by the clathrin-disassembly factor, Auxilin. These observations validate Drosophila melanogaster as a powerful model for the study of BLOC-1 function and its interactions with modifier genes.
Databáze: MEDLINE