Durable multitransgene expression in vivo using systemic, nonviral DNA delivery.

Recombinant adeno-associated virus (AAV) vectors are transforming therapies for rare human monogenic deficiency diseases. However, adaptive immune responses to AAV and its limited DNA insert capacity, restrict their therapeutic potential. HEDGES (high-level extended duration gene expression system), a nonviral DNA- and liposome-based gene delivery platform, overcomes these limitations in immunocompetent mice. Specifically, one systemic HEDGES injection durably produces therapeutic levels of transgene-encoded human proteins, including FDA-approved cytokines and monoclonal antibodies, without detectable integration into genomic DNA. HEDGES also controls protein production duration from <3 weeks to >1.5 years, does not induce anti-vector immune responses, is reexpressed for prolonged periods following reinjection, and produces only transient minimal toxicity. HEDGES can produce extended therapeutic levels of multiple transgene-encoded therapeutic human proteins from DNA inserts >1.5-fold larger than AAV-based therapeutics, thus creating combinatorial interventions to effectively treat common polygenic diseases driven by multigenic abnormalities.

Contact chemoreceptors mediate male-male repulsion and male-female attraction during Drosophila courtship.

The elaborate courtship ritual of Drosophila males is dictated by neural circuitry established by the transcription factor Fruitless and triggered by sex-specific sensory cues. Deciphering the role of different stimuli in driving courtship behavior has been limited by the inability to selectively target appropriate sensory classes. Here, we identify two ion channel genes belonging to the degenerin/epithelial sodium channel/pickpocket (ppk) family, ppk23 and ppk29, which are expressed in fruitless-positive neurons on the legs and are essential for courtship. Gene loss-of-function, cell-inactivation, and cell-activation experiments demonstrate that these genes and neurons are necessary and sufficient to inhibit courtship toward males and promote courtship toward females. Moreover, these cells respond to cuticular hydrocarbons, with different cells selectively responding to male or female pheromones. These studies identify a large population of pheromone-sensing neurons and demonstrate the essential role of contact chemosensation in the early courtship steps of mate selection and courtship initiation.

Structural characterization of glycosaminoglycans from zebrafish in different ages.

The zebrafish (Danio rerio) is a popular model organism for the study of developmental biology, disease mechanisms, and drug discovery. Glycosaminoglycans (GAGs), located on animal cell membranes and in the extracellular matrix, are important molecules in cellular communication during development, in normal physiology and pathophysiology. Vertebrates commonly contain a variety of GAGs including chondroitin/dermatan sulfates, heparin/heparan sulfate, hyaluronan and keratan sulfate. Zebrafish might represent an excellent experimental organism to study the biological roles of GAGs. A recent study showing the absence of heparan sulfate in adult zebrafish, suggested a more detailed evaluation of the GAGs present in this important model organism needed to be undertaken. This report aimed at examining the structural alterations of different GAGs at the molecular level at different developmental stages. GAGs were isolated and purified from zebrafish in different stages in development ranging from 0.5 days to adult. The content and disaccharide composition of chondroitin sulfate and heparan sulfate were determined using chemical assays, liquid chromotography and mass spectrometry. The presence of HS in adult fish was also confirmed using (1)H-NMR.