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Cancer is the leading cause of death in dogs and cats. Early diagnosis of cancer is critical for effective treatment and improving survival rates. Nematode-NOSE (N-NOSE) is a commercially available non-invasive human cancer screening test that uses the sense of smell of the nematode Caenorhabditis elegansshowing a distinct chemotactic response toward the urine of an individual with cancer compared to healthy ones. 15 types of human cancer (stomach, colon-rectum, lung, breast, pancreas, liver, prostate, uterus, esophagus, gallbladder, bile duct, kidney, urinary bladder, ovary, and oropharynx cancers) can be detected by N-NOSE.

Although some viruses have been shown to encode long non-coding RNAs (lncRNAs), how they function during their infection cycles remains elusive. We previously found an unexpectedly large number of novel transcripts, including putative lncRNAs, which were expressed from the genome of the baculovirus Bombyx morinucleopolyhedrovirus (BmNPV). To investigate the function of baculoviral antisense lncRNAs, we selected 15 BmNPV lncRNAs expressed from the baculovirus early or late promoter motif, and constructed the corresponding promoter knockout (PKO) viruses in which nucleotide substitutions were introduced at the transcription start sites of lncRNAs. We investigated the production of budded viruses (BVs) and occlusion bodies (OBs) in PKO virus-infected cultured cells and silkworm larvae. No defects in BV and OB production were observed for most of the PKO viruses, whereas KO122AS, in which an antisense lncRNA in the Bm122locus was disrupted, produced fewer OBs than the wild-type or repair virus both in cultured cells and in silkworm larvae. Northern blot analysis revealed that loss of this antisense lncRNAs reduced the amounts of the corresponding sense mRNA. These results suggest that the lncRNA transcribed from the Bm122locus might contribute to virus propagation by regulating viral gene expression. This is the first study to characterize the properties and functions of baculoviral lncRNAs.

The baculovirus ie2gene is one of the immediate early genes, and its product is known to transactivate viral promoters. However, the roles of Bombyx morinucleopolyhedrovirus (BmNPV) ie2in insect larvae are poorly understood. Here we investigated the functions of BmNPV IE2 in cultured cells and in insect larvae using two mutant viruses, BmIE2D and BmIE2CS. BmIE2D lacks the IE2 C-terminal coiled-coil domain that is required for IE2 dimerization. The other mutant BmIE2CS expresses an E3 ligase activity-deficient IE2 derivative, which is degraded more slowly compared with wild-type IE2. We found that ie2mutations had little effect on BmNPV infection in cultured cells, whereas budded virus and occlusion body production was significantly reduced in the hemolymph of B. morilarvae infected with ie2mutants. These results indicate that both dimerization and proper degradation of BmNPV IE2 are crucial steps for efficient virus growth in B. morilarvae, but not in cultured cells. Oral infection assays also revealed that the infectivity of the occluded form of ie2mutants was normal in B. morilarvae, which is inconsistent with the results reported from ie2mutants of Autographa californicaNPV. This suggests that loss of IE2 function causes virus-specific effects in host insects.