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Petroleum-based plastics (such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, etc.) as white waste have caused great concern in the environment. It is urgent to develop a kind of biodegradable, biocompatible and non-toxic materials to replace them. Herein, an environmental-friendly edible film for postharvest fruits refreshing application was prepared by combining the waste fish scale-derived gelatin, chitosan as well as CaCO3 nanoparticles. The as-prepared nanocomposite film showed the multifunctional features, such as UV absorption, antimicrobial, oxygen screening, excellent mechanical properties and non-toxic. In addition, the protein-polysaccharide based nanocomposite film was hydrophilic and can be easily washed away on fruits before eating. In order to inspect its preservative effect on fruits, longan and banana were chosen as the testing object. Our results showed that the edible multifunctional nanocomposite film can effectively extend the shelf life of longan by more than 3 days and banana by more than 5 days, compared with the control groups. Integrating natural biological macromolecules gelatin and chitosan into a multifunctional nanocomposite film with series of advantages of biodegradability, sustainability as well as multifunction is expected to be a potential preservative material for food packaging applications.

White shrimp Litopenaeus vannamei are widely cultured in the world and white spot syndrome virus (WSSV) led to huge economic losses in the shrimp industry every year. In the present study, miRNAs involved in the response of shrimp L. vannamei to WSSV infection were obtained through the Illumina HiSeq 2500 high-throughput next-generation sequencing technique. A total number of 7 known miRNAs and 54 putative novel miRNAs were obtained. Among them, 14 DEMs were identified in the shrimp infected with WSSV. The putative target genes of these DEMs were related to host immune response or signaling pathways, indicating the importance of miRNAs in shrimp against WSSV infection. The results will provide information for further research on shrimp response to virus infection and contribute to the development of new strategies for effective protection against WSSV infections.

The Asian honeybee Apis cerana is one of two bee species that have been commercially kept with immense economic value. Here we present the analysis of genomic sequence and transcriptomic exploration for A. cerana as well as the comparative genomic analysis of the Asian honeybee and the European honeybee A. mellifera. The genome and RNA-seq data yield new insights into the behavioral and physiological resistance to the parasitic mite Varroa the evolution of antimicrobial peptides, and the genetic basis for labor division in A. cerana. Comparison of genes between the two sister species revealed genes specific to A. cerana, 54.5% of which have no homology to any known proteins. The observation that A. cerana displayed significantly more vigilant grooming behaviors to the presence of Varroa than A. mellifera in conjunction with gene expression analysis suggests that parasite-defensive grooming in A. cerana is likely triggered not only by exogenous stimuli through visual and olfactory detection of the parasite, but also by genetically endogenous processes that periodically activates a bout of grooming to remove the ectoparasite. This information provides a valuable platform to facilitate the traits unique to A. cerana as well as those shared with other social bees for health improvement.

Iron is considered as an essential element for all living organisms. Therefore, limiting iron availability may be key part of the host's innate immune response to various pathogens. Ferritin is a major iron storage protein in living cells and plays an important role in iron homeostasis. One way the host can transiently reduce iron bioavailability is by ferritin over expression. In invertebrates, ferritin was found to be up-regulated after pathogens challenge and is considered to be an important element in the innate immune system. This study was designed to investigate the involvement of ferritin in shrimp Litopenaeus vannamei defense against WSSV. We discovered that the viral load of shrimp injected with recombinant ferritin protein was lower than that of control group. The suppression of ferritin by dsRNA increased susceptibility to WSSV with 3-fold high viral copies. The present study documented that ferritin protected shrimp L. vannamei from WSSV by inhibiting virus replication. We presume that ferritin reduce iron availability, leading to inhibit the activity of ribonucleotide reductase and delay the replication of virus genome. This study provided new insights into the understanding of molecular responses and defense mechanisms in shrimp against WSSV.

The translationally controlled tumor protein (TCTP) is an abundant, ubiquitous, and conserved protein which plays important roles in a number of biological processes. In the present study, the TCTP in shrimp Litopenaeus vannamei was analyzed. The TCTP of L.vannamei, a 168-amino-acid polypeptide, shares a high degree of similarity with TCTPs from other species, having two TCTP protein signatures at the 45-55 aa and 123-145 aa motif. The mRNA and protein levels from different tissues were detected with the highest in muscle and the lowest in heart among all examined tissues. In addition, temporal TCTP expression was significantly up-regulated at 16 h and 48 h following infection with white spot syndrome virus (WSSV). Lastly, silencing of TCTP with dsRNA led to a significant increase of WSSV loads. These results provide new insights into the importance of TCTP as an evolutionarily conserved molecule for shrimp innate immunity against virus infection.

Yuanyue Li,1 Congjie Dai,2 Juan Li,3 Weiwei Wang,3 Gang Song31Fisheries College, Jimei University, Fujian, China; 2School of Chemical and Life Science, Quanzhou Normal University, Fujian, China; 3Cancer Research Center, Medical College of Xiamen University, Xiamen, ChinaBackground: Growing evidence supports BH3-interacting domain death agonist (Bid) playing a dual role in DNA damage response. However, the effects of Bid on hepatocellular carcinoma (HCC) cell proliferation in response to etoposide-induced DNA damage have not been sufficiently investigated.Methods: Using a stable Bid-overexpression HCC cell line, Bid/PLC/PRF/5, overexpression of Bid promoted loss of viability in response to etoposide-induced DNA damage. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]- and BrdU (5'-bromo-2'-deoxyuridine)-labeling assays revealed that etoposide-inhibited HCC cells grew in concentration- and time-dependent manners. The phosphorylations of Akt and mitogen-activated protein kinases (MAPKs) in response to etoposide-induced DNA damage were analyzed by Western blotting.Results: The survival rates of 100 µM etoposide on the cells with control vector and Bid/PLC/PRF/5 at 48 hours amounted to 71% ± 0.75% and 59% ± 0.60% with MTT assay, and similar results of 85% ± 0.08% and 63% ± 0.14% with BrdU-labeling assay respectively. Moreover, overexpression of Bid sensitized the cells to apoptosis at a high dose of etoposide (causing irreparable damage). However, it had little effect on the proliferation at a low dose of etoposide (repairable damage). Furthermore, the phosphorylation status of Akt and MAPKs were investigated. Overexpression of Bid suppressed the activation of Akt with respect to etoposide-induced DNA damage. Similar to Akt, the levels of phosphorylated p38 and phosphorylated c-Jun were attenuated by Bid-overexpression. On the contrary, the level of phosphorylated ERK1/2 was sustained at a high level, especially in Bid/PLC/PRF/5 cells.Conclusion: Taken together, these results suggest that overexpression of Bid suppressed the activation of Akt, p38, and c-Jun, and promoted the activation of ERK1/2 induced by etoposide, suggesting that the promotion of ERK1/2 activation may have a negative effect on Bid-mediated HCC DNA damage induced by etoposide.Keywords: HCC, mitogen-activated protein kinases, BH3-interacting domain death agonist