Project description:Oryctes rhinoceros nudivirus (OrNV) is a dsDNA virus which has been used as a biocontrol agent to suppress Coconut Rhinoceros Beetle (Oryctes rhinoceros) in Southeast Asia and the Pacific Islands. Recently a new wave of O. rhinoceros incursions in Oceania is thought to be related to the presence of low virulence isolates of OrNV or virus tolerant haplotypes of beetles. Here, chronically infected beetles were collected from the Philippines, Fiji, PNG and the Solomon Islands (SI). RNAseq was performed to investigate the global viral gene expression profiles and comparative genomic analysis of structural variations. Maximum likelihood phylogenic analysis indicated that OrNV strains from the SI and the Philippines are closely related to while OrNV strains from PNG and Fiji formed a distinct adjacent clade. We detected several polymorphic sites with a frequency higher than 35% in 892 positions of the viral genome. Non-synonymous mutations were detected in several hypothetical proteins, and 15 nudivirus core genes such as gp034, lef-8, lef-4 and vp91. We found limited evidence of variation in viral gene expression among geographic populations. Only a few genes such as gp01, gp022 and gp107 were differentially expressed among different strains. Additionally, small RNA sequencing from SI population suggests that OrNV is targeted by the host RNA interference (RNAi) response with abundant 21nt small RNAs. Some of these structural changes are specific to the geographic population and could be related to particular phenotypic characteristics of the strain, such as viral pathogenicity or transmissibility, and this requires further investigation.
Project description:Efforts to implement effective assisted reproductive technologies (ART) to extricate the northern white rhinoceros (NWR; Ceratotherium simum cottoni) from extinction, could be unconventionally offset from studies carried out using the southern white rhinoceros (Ceratotherium simum simum) as a relative model species. The bi-directional communication and critical transport of regulatory molecules controlling follicular growth and oocyte development are in part mediated through extracellular vesicles (EVs), which encompass a highly conserved and advanced paracrine signaling mechanism important in shuttling unique cargo such as microRNAs (miRNAs). In this study, critical miRNAs for follicular development were identified, proposing novel approaches using EV-mediated miRNA to possibly improve the in vitro technologies outcome in a multitude of species.
