Although mosquitoes are major transmission vectors for pathogenic arboviruses, viral infection has little impact on mosquito health. This immunity is caused in part by mosquito RNA interference (RNAi) pathways that generate antiviral small interfering RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). RNAi also maintains genome integrity by potently repressing mosquito transposon activity in the germline and soma. However, viral and transposon small RNA regulatory pathways have not been systematically examined together in mosquitoes. Therefore, we developed an integrated mosquito small RNA genomics (MSRG) resource that analyzes the transposon and virus small RNA profiles in mosquito cell cultures and somatic and gonadal tissues across four medically important mosquito species. Our resource captures both somatic and gonadal small RNA expression profiles within mosquito cell cultures, and we report the evolutionary dynamics of a novel Mosquito-Conserved piRNA Cluster Locus (MCpiRCL) made up of satellite DNA repeats. In the larger culicine mosquito genomes we detected highly regular periodicity in piRNA biogenesis patterns coinciding with the expansion of Piwi pathway genes. Finally, our resource enables detection of cross talk between piRNA and siRNA populations in mosquito cells during a response to virus infection. The MSRG resource will aid efforts to dissect and combat the capacity of mosquitoes to tolerate and spread arboviruses.

Electrocatalytic water oxidation by the catalyst, ruthenium 2,2′bipyridine-6,6′-dicarboxylate (bda) bis-isoquinoline (isoq), [Ru(bda)(isoq) 2 ], 1, was investigated at metal oxide electrodes surface-derivatized with electron transfer (ET) mediators. At indium-doped tin oxide (ITO) in pH 7.2 in H 2 PO 4 − / HPO 4 2− buffers in 0.5 M NaClO 4 with added acetonitrile (MeCN), the catalytic activity of 1 is enhanced by the surface-bound redox mediators [Ru (4,4′-PO 3 H 2bpy)(4,4′-R-bpy) 2 ] 2+ (RuPbpyR 2 2+ , R = Br, H, Me, or OMe, bpy = 2,2′bipyridine). Rate-limiting ET between the Ru 3+ form of the mediator and the Ru IV (O) form in the [Ru V/IV (O)] +/0 couple of 1 is observed at relatively high concentrations of HPO 4 2− buffer base under conditions where O•••O bond formation is facilitated by atom-proton transfer (APT). For the solution [Ru(bpy) 3 ] 3+/2+ mediator couple and 1 as the catalyst, catalytic currents vary systematically with the concentration of mediator and the HPO 4 2− buffer base concentration. Electron transfer mediation of water oxidation catalysis was also investigated on nanoparticle TiO 2 electrodes co-loaded with catalyst [Ru(bda)(py-4-O(CH 2 ) 3 -PO 3 H 2 ) 2 ], 2, (py = pyridine) and RuPbpyR 2 2+ (R = H, Me, or OMe) with an interplay between rate-limiting catalyst oxidation and rate-limiting O•••O bond formation by APT. Lastly, the co-loaded assembly RuPbpyR 2 2+ + 2 has been investigated in a dye-sensitized photoelectrosynthesis cell for water splitting.

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Background: Host individuals represent an arena in which pathogens compete for resources and transmission opportunities, with major implications for the evolution of virulence and the structure of populations. Studies to date have focused on competitive interactions within pathogen species, and the level of antagonism tends to increase with the genetic distance between competitors. Anther-smut fungi, in the genus Microbotryum, have emerged as a tractable model for within-host competition. Here, using two pathogen species that are frequently found in sympatry, we investigated whether the antagonism seen among genotypes of the same species cascades up to influence competition among pathogen species.

1Although mosquitoes are major transmission vectors for pathogenic arboviruses, 2 viral infection has little impact on mosquito health. This immunity is due in part to 3 mosquito RNA interference (RNAi) pathways that generate antiviral small interfering 4 RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). RNAi also maintains genome 5 integrity by potently repressing mosquito transposon activity in the germline and soma. 6 However, viral and transposon small RNA regulatory pathways have not been 7 systematically examined together in mosquitoes. Therefore, we developed an integrated 8 Mosquito Small RNA Genomics (MSRG) resource that analyzes the transposon and 9 virus small RNA profiles in mosquito cell cultures and somatic and gonadal tissues 10 across four medically important mosquito species. Our resource captures both somatic 11 and gonadal small RNA expression profiles within mosquito cell cultures, and we report 12 the evolutionary dynamics of a novel Mosquito-Conserved piRNA Cluster Locus 13 (MCpiRCL) composed of satellite DNA repeats. In the larger culicine mosquito genomes 14 we detected highly regular periodicity in piRNA biogenesis patterns coinciding with the 15