Drosophila cell team at the DGRC reports integrase-mediated cassette exchange approach to production of clonal transgenic fly cell lines

Lucy Cherbas1, Jennifer Hackney, Lei Gong, Claire Salzer, Eric Mauser, Dayu Zhang and Peter Cherbas. Tools for Targeted Genome Engineering of Established Drosophila Cell Lines.
Early online in G3.

From the abstract: "We describe an adaptation of ΦC31 integrase-mediated targeted cassette exchange for use in Drosophila cell lines. Single copies of an attP-bounded docking platform carrying a GFP-expression marker, with or without insulator elements flanking the attP sites, were inserted by P-element transformation into the Kc167 and Sg4 cell lines; each of the resulting docking site lines carries a single mapped copy of one of the docking platforms. ... We describe procedures for isolating cells carrying the substitutions ... When compared with clonal lines made by traditional transformation methods ... targeted insertion lines give more uniform expression, lower basal expression and higher induction ratios. Targeted substitution, though intricate, affords results that should greatly improve comparative expression assays – a major emphasis of cell-based studies." 

RNAi-based screen for interaction with chd1

Sharon Kim, Lakshmi Bugga, Eugenie S. Hong, Rebecca Zabinsky, Rebecca G. Edwards, Parimal A. Deodhar and Jennifer A. Armstrong. An RNAi-Based Candidate Screen for Modifiers of the CHD1 Chromatin Remodeler and Assembly Factor in Drosophila melanogaster.
Early online at G3.

From the abstract: "... CHD1 ... is present at active genes where it participates in histone turnover and recycling during transcription. ... We found that over-expression of the CHD1 results in defects in wing development and utilized this fully penetrant and reliable phenotype to conduct a small-scale RNAi-based candidate screen to identify genes that functionally interact with chd1 in vivo. ..."

in vivo RNAi used to validate at gene level hits in genome-wide deficiency screen for enhancers and suppressors of Na (+) /K (+) ATPase alleles

Talsma AD, Chaves JF, LaMonaca A, Wieczorek ED, Palladino MJ. Genome-wide screen for modifiers of Na (+) /K (+) ATPase alleles identifies critical genetic loci. Mol Brain. 2014 Dec 5;7:89. doi: 10.1186/s13041-014-0089-3. PMID: 25476251; PMCID: PMC4302446.

From the abstract: "Mutations affecting the Na (+) / K (+) ATPase (a.k.a. the sodium-potassium pump) genes cause conditional locomotor phenotypes in flies and three distinct complex neurological diseases in humans. More than 50 mutations have been identified affecting the human ATP1A2 and ATP1A3 genes that are known to cause rapid-onset Dystonia Parkinsonism, familial hemiplegic migraine, alternating hemiplegia of childhood, and variants of familial hemiplegic migraine with neurological complications including seizures and various mood disorders. In flies, mutations affecting the ATPalpha gene have dramatic phenotypes including altered longevity, neural dysfunction, neurodegeneration, myodegeneration, and striking locomotor impairment. ... We performed a genome-wide deficiency screen ... to identify novel modifier loci. A secondary screen confirmed allele-specificity of the interactions and many of the interactions were mapped to single genes and subsequently validated. We successfully identified 64 modifier loci and used classical mutations and RNAi to confirm 50 single gene interactions. ... These data demonstrate there are many loci capable of modifying ATPalpha dysfunction, which may provide the basis for modifying migraine, locomotor and seizure dysfunction in animals."