Depletion of UBC9 Causes Nuclear Defects during the Vegetative and Sexual Life Cycles in Tetrahymena thermophila

Oral delivery of dsHvlwr is a feasible method for managing the pest Henosepilachna vigintioctopunctata (Coleoptera: Coccinellidae)

RNA interference (RNAi) techniques have emerged as powerful tools that facilitate development of novel management strategies for insect pests, such as Henosepilachna vigintioctopunctata (Coleoptera: Coccinellidae), which is a major pest of solanaceous plants in Asia. In this study, the potential of oral delivery of in vitro-synthesized and bacterially expressed double-stranded H. vigintioctopunctata lesswright (lwr) gene (dsHvlwr) to manage of H. vigintioctopunctata was investigated. Our results showed that the gene Hvlwr had a 480-bp open reading frame and encoded a 160-amino acid protein. Hvlwr expression levels were greater in the fat body than other tissue types. Hvlwr silencing led to greater H. vigintioctopunctata mortality rates and appeared to be time- and partially dose-dependent, likely as a result of the number of hemocytes increasing with dsRNA concentration, but decreasing with time. Bacterially expressed dsHvlwr that was applied to leaf discs caused 88%, 66%, and 36% mortality in 1st instars, 3rd instars, and adults after 10, 10, and 14 d, respectively; when applied to living plants, there was greater mortality in 1st and 3rd instars, but there was no effect on adults. Furthermore, dsHvlwr led to improved plant protection against H. vigintioctopunctata. Our study shows an effective dietary RNAi response in H. vigintioctopunctata and that Hvlwr is a promising RNAi target gene for control of this pest species.

Comparative analysis of iTRAQ-based proteome profiles of Schistosoma japonicum female worms coming from single-sex infections and bisexual infections

In schistosomiasis, eggs produced by bisexual infected mature female schistosome worms (FMS) are the main cause of pathological damage to the host and the dissemination of the disease. Single-sex infected female worms (FSS) cannot completely develop to sexual maturity or produce normal eggs. In this study, isobaric tags for relative and absolute quantitation (iTRAQ)-coupled LC-MS/MS was used to explore the proteome of FSS and FMS of Schistosoma japonicum. A total of 1477 differentially expressed proteins (fold change >1.2, P < .05) between FSS and FMS were identified. Bioinformatics analysis indicated that FMS expressed more proteins related to biosynthetic processes, such as eggshell synthesis, ribosomal synthesis, protein folding, cellular detoxification, and metabolic processes such as protein metabolism and glucose metabolism, whereas more proteins related to locomotion and oxidative phosphorylation were expressed in FSS. Our identification and analysis of differentially expressed proteins between FMS and FSS provides new insights to elucidate the molecular biological mechanisms of female worm sexual maturation and reproduction. SIGNIFICANCE: Female Schistosome worms must maintain constant pairing contact with male worms for differentiation of their reproductive organs. Mature female worms can produce infectious eggs, cause serious pathological damage to the host and the dissemination of the disease. Unpaired female worms remain small and sexually immature; they do not spawn normally. In this study, iTRAQ-coupled LC-MS/MS was used to explore the whole proteome of single-sex infected female worms (FSS) and bisexual infected mature female worms (FMS) of Schistosoma japonicum. 1477 differentially expressed proteins (DEPs) between FSS and FMS were identified and analyzed. Further research on DEPs' functions in schistosome sexual maturation and reproductive development might provide theoretical bases to explore female maturation and spawning.

Function of the lesswright (lwr) gene in the growth, development, and reproduction of Schistosoma japonicum

The lesswright (lwr) gene and its products are essential molecules in mitosis, DNA repair, and embryo formation in many eukaryotes. In this study, immunohistochemical analysis revealed that the Lwr protein was located in the internal tissues and the surface layer of the adult Schistosoma japonicum (Sj) worms. The mRNA expression levels of SjLwr at different points were evaluated by quantitative real-time RT-PCR. The expression of SjLwr peaked at 14 days and then decreased thereafter. SjLwr expression was relatively more stable in male worms than in female worms. The functions of SjLwr were explored by siRNA-based gene silencing with a simple soaking method. The results showed that knockdown of the SjLwr gene impaired the growth and development of S. japonicum in mice, as well as survival, morphology, reproductive capacity, and egg vitality. These observations imply that SjLwr presents a novel target for the development of immuno- and/or small molecule-based therapeutics for the control and treatment of schistosome infections.