In vivo role of nectin-1 in entry of herpes simplex virus type 1 (HSV-1) and HSV-2 through the vaginal mucosa

Herpes simplex virus type 2 (HSV-2) is transmitted through the genital mucosa during sexual encounters. In recent years, HSV-1 has also become commonly associated with primary genital herpes. The mechanism of viral entry of HSV-1 and HSV-2 in the female genital tract is unknown. In order to understand the molecular interactions required for HSV entry into the vaginal epithelium, we examined the expression of herpesvirus entry mediator nectin-1 in the vagina of human and mouse at different stages of their hormonal cycle. Nectin-1 was highly expressed in the epithelium of human vagina throughout the menstrual cycle, whereas the mouse vaginal epithelium expressed nectin-1 only during the stages of the estrous cycle in which mice are susceptible to vaginal HSV infection. Furthermore, the ability of nectin-1 to mediate viral entry following intravaginal inoculation was examined in a mouse model of genital herpes. Vaginal infection with either HSV-1 or HSV-2 was blocked by preincubation of the virus with soluble recombinant nectin-1. Viral entry through the vaginal mucosa was also inhibited by preincubation of HSV-2 with antibody against gD. Together, these results suggest the importance of nectin-1 in mediating viral entry for both HSV-1 and HSV-2 in the genital mucosa in female hosts.     

Isolation and characterization of a novel mycovirus infecting an edible mushroom,Grifola frondosa

Grifola frondosa (Maitake mushroom) is an important cultivated mushroom due to its medicinal and nutrient values. In this study, we isolated and characterized a novel partitivirus (named Grifola frondosa partitivirus 1, GfPV1) infecting a standard G. frondosa strain Gf-N2. This virus has a two-segmented dsRNA genome (dsRNA1 and dsRNA2) with nucleotide lengths of 2.3 and 2.2 kbp, respectively. The coding strand of dsRNA1 and dsRNA2 segments carries single open reading frame encoding RNA-dependent RNA polymerase (RdRp) and a coat protein (CP), respectively. BLAST searches and phylogenetic analyses showed that GfPV1 is most closely related to a betapartitivirus, Lentinula edodes partitivirus 1 (RdRp <70% and CP <60% amino acid sequence identities), but the sequence divergence suggests that GfPV1 is classifiable as a new member of the genus Betapartitivirus, family Partitiviridae. The presence of GfPV1 does not affect colony morphology and fruiting body development of G. frondosa. This is the first report investigating the effects of a mycovirus infection on the colony morphology and fruiting body development of G. frondosa. Interestingly, GfPV1 accumulations markedly decreased along with the fruiting body maturation stages, suggesting the inhibition of virus multiplication during sexual phase of the G. frondosa life cycle.     

Settlement of Planulae of the Moon Jellyfish Aurelia aurita onto Hydrophilic Polycarbonate Plates Modified by Atmospheric Plasma Treatment

It has been reported that planula larvae of some jellyfish prefer artificial substrates for settlement. This research focused on the relationship between the settlement of planulae and the wettability of artificial substrate surfaces. We used atmospheric plasmas to change the wettability of the surfaces of polycarbonate (PC) plates because plasma treatment has no chemical side effects. The treatment made the surfaces hydrophilic, as evidenced by the decrease of contact angle from 85° to 35°. X-ray photoelectron spectroscopy revealed that the change of wettability of the PC plates could be attributed to N₂, which was probably ionized in the air above the plates. Scanning electron microscopy revealed no difference in the surface morphology of the plates before and after plasma treatment. Results of bioassays using treated PC plates showed that planulae tended to preferentially settle on hydrophobic surfaces.     

Germ cell mutations of the ascidian Ciona intestinalis with TALE nucleases

Summary: Targeted mutagenesis of genes‐of‐interest, or gene‐knockout, is a powerful method to address the functions of genes. Engineered nucleases have enabled this approach in various organisms because of their ease of use. The ascidian Ciona intestinalis is an excellent organism to analyze gene functions by means of genetic technologies. In our previous study, we reported mutagenesis of Ciona somatic cells with TALE nucleases (TALENs) by electroporating expression constructs. In this study, we report germ cell mutagenesis of Ciona by microinjecting mRNAs encoding TALENs. TALEN mRNAs introduced mutations to target genes in both somatic and germ cells. TALEN‐mediated mutations in the germ cell genome were inherited by the next generation. We conclude that knockout lines of Ciona that have disrupted target genes can be established through TALEN‐mediated germ cell mutagenesis. genesis 52:431–439, 2014. © 2014 Wiley Periodicals, Inc.     

Tet1 and Tet2 regulate 5-hydroxymethylcytosine production and cell lineage specification in mouse embryonic stem cells

TET family enzymes convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) in DNA. Here, we show that Tet1 and Tet2 are Oct4-regulated enzymes that together sustain 5hmC in mouse embryonic stem cells (ESCs) and are induced concomitantly with 5hmC during reprogramming of fibroblasts to induced pluripotent stem cells. ESCs depleted of Tet1 by RNAi show diminished expression of the Nodal antagonist Lefty1 and display hyperactive Nodal signaling and skewed differentiation into the endoderm-mesoderm lineage in embryoid bodies in?vitro. In Fgf4- and heparin-supplemented culture conditions, Tet1-depleted ESCs activate the trophoblast stem cell lineage determinant Elf5 and can colonize the placenta in midgestation embryo chimeras. Consistent with these findings, Tet1-depleted ESCs?form aggressive hemorrhagic teratomas with increased endoderm, reduced neuroectoderm, and ectopic appearance of trophoblastic giant cells. Thus, 5hmC is an epigenetic modification associated with the pluripotent state, and Tet1 functions to regulate the lineage differentiation potential of ESCs.