Identification of a Yorkie homolog from Litopenaeus vannamei as a negative regulator in anti-WSSV immune response.

Hippo signaling pathway is a serine threonine kinase cascade that is evolutionary conserved with well-established roles in organ size control, development, tumorigenesis and immunity. As its core molecule, Yorkie also plays an important role against pathogen. In this study, we cloned and characterized a Yorkie homolog from Litopenaeus vannamei, designed as LvYKI, which has a 1650 bp open reading frame. It has the characterized domains of Yokie family, and displayed to be close to the insects and crustacean. Quantitative Real-time PCR showed that LvYKI had different regulatory mechanisms in different tissues. The transcriptional level of Lvyki was down-regulated in gill, while up-regulated in hepatopancreas post white spot syndrome virus (WSSV) infection. Moreover, the expression and phosphorylation of LvYKI was reduced upon WSSV infection, which indicated that LvYKI was involved in WSSV infection. Furthermore, RNAi was performed to evaluate the role of LvYKI in shrimp immune responses. Knocking down of Lvyki resulted in inhibition of the transcription of WSSV gene ie1 and vp28, and delayed mortality of shrimp post WSSV infection. Meanwhile, the apoptosis of hemocyte was increased as well. All results suggested that shrimp can promote apoptosis to resist WSSV infection mediated by down-regulation of LvYKI. In addition, it was found that LvYKI could interact with Lvß-catenin, which cross-linked the Wnt and Hippo signaling pathway in innate immunity. Conclusively, our study provided clues that LvYKI plays an important role in the interaction between shrimp and virus. It will promote our understanding of the molecular mechanism in innate immunity.

Polarization-selective ultra-broadband super absorber.

While a broadband metamaterial perfect absorber (MPA) has been implemented and proposed intensively in recent years, an ultra-broadband perfect absorber with polarization selectivity has not been realized in literature. In this work, we propose a configuration of polarization-selective (PS) MPA with ultra-wide absorption bandwidth. The aluminum wire grid is integrated on top of the ultrathin-metal-dielectric stacking. The transverse electric (TE) wave is blocked due to the requirement of zero tangential electric field at the metal surface. The transverse magnetic field can pass the aluminum wire-grids because the normal electric field can be supported by the surface charge density at the metal surface, and full absorption of the TM wave is accomplished by the metal-dielectric stacking beneath. Theoretical calculation using rigorously coupled wave analysis demonstrates the wavelength selectivity from λ = 1.98µm to λ = 11.74µm where the TE absorption is <0.04 while TM absorption is >0.95, using 300 nm thick aluminum (Al) wire grid with 16-pair SiO2/Ti stacking. Additionally, the design is wavelength scalable by adjusting the dielectric thickness (tSiO2) and the wire grid period (P) and height (t). The experimental result is demonstrated using Al grids and Ti/SiO2, and the measured result fully supports the calculated prediction.

De novo transcriptome assembly of the deep-sea hydrothermal vent, shrimp Rimicaris exoculate (Crustacea: Decapoda), from the south Mid-Atlantic Ridge.

The deep-sea hydrothermal vent is a special ecosystem, which is different from terrestrial or coastal ecosystems. Rimicaris exoculata, which adapts well to several deep-sea hydrothermal vent environments, is the ideal model for studying hydrothermal vent fauna. In the present study, we obtained R. exoculata from a newly found hydrothermal vent in the south Mid-Atlantic Ridge, and the Illumina next-generation sequencing and de novo assembly were performed by Beijing Genomics Institution. A total of 17,258 annotated Unigenes were obtained. Several Unigenes associated with sulfide metabolism, which might contribute to well adaptation to high concentration of sulfide for R. exoculata, were annotated. This study is the first report on the high-throughput sequencing of R. exoculata. Our data can allow for further studies on the ability of R. exoculata adaptation to harsh conditions and provide abundant gene resources for research and development.