Wednesday, May 17, 2017

RNAi screen focused on chaperone function in the fly eye

Raut S, Mallik B, Parichha A, V A, Sahi C, Kumar V. RNAi-Mediated Reverse Genetic Screen Identified Drosophila Chaperones Regulating Eye and Neuromuscular Junction Morphology. G3 (Bethesda). 2017 May 12. pii: g3.117.041632. PMID: 28500055.

From the abstract: "Accumulation of toxic proteins in neurons have been linked with the onset of neurodegenerative diseases ... Molecular chaperones help protein folding and resolubilization of unfolded proteins thereby reducing the protein aggregation stress. While most of the chaperones are expressed in neurons, their functional relevance largely remains unknown. Here, using bioinformatics analysis, we identified 95 Drosophila chaperones and classified them into seven different classes. Ubiquitous actin5C-Gal4 mediated RNAi knockdown revealed that about 50% of the chaperones are essential in Drosophila[.] Knocking down these genes in eyes revealed that about 30% of the essential chaperones are crucial for eye development. ..."

Monday, February 13, 2017

Genome-wide fly cell RNAi screen related to Wolbachia infection

White PM, Serbus LR, Debec A, Codina A, Bray W, Guichet A, Lokey RS, Sullivan W. Reliance of Wolbachia on High Rates of Host Proteolysis Revealed by a Genome-Wide RNAi Screen of Drosophila Cells. Genetics. 2017 Feb 3. pii: genetics.116.198903. PMID: 28159754.

From the abstract: "Wolbachia are gram-negative, obligate, intracellular bacteria carried by a majority of insect species worldwide. Here we use a Wolbachia-infected Drosophila cell line and genome-wide RNAi screening to identify host factors that influence Wolbachia titer. .. we identified 36 candidate genes that dramatically reduced Wolbachia titer and 41 that increased Wolbachia titer. ... knockdown of 7 genes in the host ubiquitin and proteolysis pathways significantly reduced Wolbachia titer. To test the in vivo relevance of these results, we found that drug and mutant inhibition of proteolysis reduced levels of Wolbachia in the Drosophila oocyte ... Given Wolbachia lack essential amino acid biosynthetic pathways, the reliance of Wolbachia on high rates of host proteolysis via ubiquitination and the ERAD pathways may be a key mechanism for provisioning Wolbachia with amino acids. In addition, the reliance of Wolbachia on the ERAD pathway and disruption of ER morphology suggests a previously unsuspected mechanism for Wolbachia's potent ability to prevent RNA virus replication."

Tuesday, January 24, 2017

RNAi and proteomics study identifies glial genes required for behavior

Ng FS, Sengupta S, Huang Y, Yu AM, You S, Roberts MA, Iyer LK, Yang Y, Jackson FR. TRAP-seq Profiling and RNAi-Based Genetic Screens Identify Conserved Glial Genes Required for Adult Drosophila Behavior. Front Mol Neurosci. 2016 Dec 22;9:146. PMID: 28066175; PMCID: PMC5177635.

From the abstract: "... Glial astrocytes and glia-neuron signaling ... have important modulatory functions in sleep, circadian behavior, memory and plasticity. To better understand mechanisms of glia-neuron signaling in the context of behavior, we have conducted cell-specific, genome-wide expression profiling of adult Drosophila astrocyte-like brain cells and performed RNA interference (RNAi)-based genetic screens ... Glial-specific expression of 653 RNAi constructs targeting 318 genes identified multiple factors associated with altered locomotor activity, circadian rhythmicity and/or responses to mechanical stress (bang sensitivity). ... These results strongly support the idea that glia-neuron communication is vital for adult behavior."