The human gene BLOC1S1 has been proposed as a candidate susceptibility locus for schizophrenia. This gene encodes a component of the multi-subunit protein complex BLOC-1 (biogenesis of lysosomal organelles complex 1). There is a single orthologous gene in Drosophila, Dmel\Blos1, for which classical loss-of-function alleles, RNAi-targeting constructs, and alleles caused by insertional mutagenesis have been generated. BLOC1S1 has also been associated with Hermansky-Pudlak syndrome (FBhh0000221).
The human BLOC1S1 gene has not been introduced into flies.
Loss-of-function mutations of Blos1 result in defects in behavior, learning, and neurophysiology. Phenotypes of homozygous loss-of-function alleles of Blos1 were compared to those of Dmel\Dysb, which encodes another subunit the BLOC-1 complex. Similar phenotypes, including impaired neurotransmitter release, synapse morphology, and homeostatic plasticity at the larval neuromuscular junction, and impaired olfactory habituation were observed for both; these phenotypes are also observed for compound heterozygotes involving LOF alleles of the two genes (see FBhh0000527). Physical interactions and additional genetic interactions of Dmel\Blos1 have been described; see below and in the Blos1 gene report.
Based in part on work in flies, the human genes DTNBP1 and BLOC1S1, subunits of the BLOC-1 complex orthologous to Dmel\Dysb and Dmel\Blos1, are both postulated to have an association with Hermansky-Pudlak syndrome and to contribute to susceptibility to schizophrenia.
[updated Jul. 2017 by FlyBase; FBrf0222196]
See also 'Schizophrenia: Symptoms, causes, and treatments' (http://www.medicalnewstoday.com/articles/36942.php).
Schizophrenia is a psychosis, a disorder of thought and sense of self. Although it affects emotions, it is distinguished from mood disorders in which such disturbances are primary. Similarly, there may be mild impairment of cognitive function, and it is distinguished from the dementias in which disturbed cognitive function is considered primary. Schizophrenia often develops in young adults who were previously normal, and is characterized by a constellation of symptoms including hallucinations and delusions (psychotic symptoms) and symptoms such as severely inappropriate emotional responses, disordered thinking and concentration, erratic behavior, as well as social and occupational deterioration (Andreasen, 1995; pubmed:7637483). [from MIM:181500; 2017.04.18]
The protein encoded by the BLOC1S1 gene is a component of the multisubunit protein complex BLOC-1 (biogenesis of lysosomal organelles complex 1). Among other functions, the BLOC-1 complex is required to target membrane protein cargos into vesicles assembled at cell bodies for delivery into neurites and nerve terminals; it is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system. [from Gene Cards, BLOC1S1; 2017.04.18]
BLOC1S1 is a component of the ubiquitously expressed BLOC1 multisubunit protein complex. BLOC1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules (Starcevic and Dell'Angelica, 2004; pubmed:15102850). [from MIM:601444; 2017.04.18]
One to one: 1 human to 1 Drosophila
High-scoring ortholog of human BLOC1S1 (1 Drosophila to 1 human). Dmel\Blos1 shares 58% identity and 76% similarity with the human gene.
