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MAF1 is a global suppressor of RNA polymerase III-dependent transcription, and is conserved from yeast to human. Growing evidence supports the involvement of MAF1 in the immune response of mammals, but its biological functions in fish are unknown. We isolated and characterized Maf1 from the olive flounder Paralichthys olivaceus (PoMaf1). The coding region of PoMaf1 comprised 738 bp encoding a 245-amino-acid protein. The deduced PoMAF1 amino acid sequence shared features with those of MAF1 orthologues from vertebrates. PoMaf1 mRNA was detected in all tissues examined, and the levels were highest in eye and muscle tissue. The PoMaf1 mRNA level increased during early development. In addition, the PoMaf1 transcript level decreased during viral hemorrhagic septicemia virus (VHSV) infection of flounder hirame natural embryo (HINAE) cells. To investigate the role of PoMaf1 in VHSV infection, single-cell-derived PoMaf1 knockout HINAE cells were generated using the clustered regularly interspaced short palindromic repeats/CRISPR-associated-9 (CRISPR/Cas9) system, and cell clones with complete disruption of PoMaf1 were selected. PoMaf1 disruption increased the VHSV glycoprotein (G) mRNA levels during VHSV infection of HINAE cells, implicating PoMAF1 in the immune response to VSHV infection. To our knowledge, this is the first study to characterize fish Maf1, which may play a role in the response to viral infection.

Alzheimer’s disease is a neurodegenerative disease characterized by the impairment of cognitive function and loss of memory, affecting millions of individuals worldwide. With the dramatic increase in the prevalence of Alzheimer’s disease, it is expected to impose extensive public health and economic burden. However, this burden is particularly heavy on the caregivers of Alzheimer’s disease patients eliciting neuropsychiatric symptoms that include mood swings, hallucinations, and depression. Interestingly, these neuropsychiatric symptoms are shared across symptoms of bipolar disorder, schizophrenia, and major depression disorder. Despite the similarities in symptomatology, comorbidities of Alzheimer’s disease and these neuropsychiatric disorders have not been studied in the Alzheimer’s disease model. Here, we explore the comprehensive changes in gene expression of genes that are associated with bipolar disorder, schizophrenia, and major depression disorder through the microarray of an Alzheimer’s disease animal model, the forebrain specific PSEN double knockout mouse. To analyze the genes related with these three neuropsychiatric disorders within the scope of our microarray data, we used selected 1207 of a total of 45,037 genes that satisfied our selection criteria. These genes were selected on the basis of 14 Gene Ontology terms significantly relevant with the three disorders which were identified by previous research conducted by the Psychiatric Genomics Consortium. Our study revealed that the forebrain specific deletion of Alzheimer’s disease genes can significantly alter neuropsychiatric disorder associated genes. Most importantly, most of these significantly altered genes were found to be involved with schizophrenia. Taken together, we suggest that the synaptic dysfunction by mutation of Alzheimer’s disease genes can lead to the manifestation of not only memory loss and impairments in cognition, but also neuropsychiatric symptoms.

Many amphibian species around the world, except in Asia, suffer morbidity and mortality when infected by the emerging infectious pathogenBatrachochytrium dendrobatidis(Bd). A lineage of the amphibian chytrid fungus isolated from South Korean amphibians (BdAsia-1) is evolutionarily basal to recombinant global pandemic lineages (BdGPL) associated with worldwide amphibian population declines. In Asia, the Bd pathogen and its amphibian hosts have coevolved over 100 years or more. Thus, resilience of Asian amphibian populations to infection might result from attenuated virulence of endemic Bd lineages, evolved immunity to the pathogen or both. We compared susceptibilities of an Australasian amphibian,Litoria caerulea, known to lack resistance to BdGPL, with those of three Korean species,Bufo gargarizans,Bombina orientalisandHyla japonica, after inoculation with BdAsia-1, BdGPL or a blank solution. Subjects became infected in all experimental treatments but Korean species rapidly cleared themselves of infection, regardless of Bd lineage. They survived with no apparent secondary effects. By contrast,L. caerulea, after infection by either BdAsia-1 or BdGPL, suffered deteriorating body condition and carried progressively higher Bd loads over time. Subsequently, most subjects died. Comparing their effects onL. caerulea, BdAsia-1 induced more rapid disease progression than BdGPL. The results suggest that genomic recombination with other lineages was not necessary for the ancestral Bd lineage to evolve hypervirulence over its long period of coevolution with amphibian hosts. The pathogen's virulence may have driven strong selection for immune responses in endemic Asian amphibian host species.

Although the classic interpretation of Heinrich events being produced by internal Laurentide ice-sheet oscillations (1) had some deficiencies, its simplicity permitted it to survive 2 decades. However, recent articles finally shed light on the mystery of how Heinrich events are triggered. In PNAS, Marcott et al. (2) reported Mg/Ca data from the northwest Atlantic Ocean revealing an AMOC (Atlantic meridional overturning circulation) slowdown accompanied by a large subsurface warming that occurred more than 1,000 years before Heinrich events. The crux, indeed, resided in the subsurface of the ocean. Thanks to recent observations around Antarctica, the poorly understood coupled effects between ocean and ice-sheet dynamics have been revealed to be crucial for understanding past massive iceberg purges. In this way, the observed control that a warming ocean exerts on the ice-streams regime (3), combined with the confirmed anticipation of an AMOC slowdown (4) and a large subsurface warming (2), clearly indicates a climatic precursor for Heinrich events. The scenario can thus be summarized as follows (Fig. 1 illustrates the mechanism specifically for Heinrich event 1):

A Gram-negative, aerobic bacterium, designated as SH-1T, was isolated from the gut content of a whiteleg shrimp, Litopenaeus vannamei collected in a shrimp farm in South Korea. The bacterial cells were ovoid rod-shaped, non-motile, oxidase-positive and catalase-negative. Growth was observed at 20–35 °C (optimum, 30 °C), pH 5.0–9.5 (pH 8.5) and in the presence of 0–6 % (w/v) NaCl (2–3 %). The major polar lipids were phosphatidylglycerol, phosphatidylinositolmannoside, unidentified aminolipid and two unidentified lipids. The G+C content was 66.1 mol% and the predominant respiratory quinone was Q-10. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain SH-1T was placed in a distinct clade with Primorskyibacter marinus PX7T (96.97 % sequence similarity), Pontibaca methylaminivorans DSM 21219T (96.03 %) and Pelagivirga sediminicola BH-SD19T (95.02 %) in the family Rhodobacteraceae and distantly related with them to be a new genus. The digital DNA–DNA hybridization (dDDH), average nucleotide identity (ANI) and average amino acid identity (AAI) values calculated from whole-genome-sequence comparison between the SH-1T and the close species were in the ranges of 19.0–19.8, 73.8–74.9 and 64.1–65.9 %, respectively. Based on the polyphasic analysis presented in this study, we suggest that strain SH-1T represents a novel genus and species in the family Rhodobacteraceae , for which the name Pukyongiella litopenaei gen. nov., sp. nov. is proposed. The type strain of Pukyongiella litopenaei is SH-1T (=KCTC 62276T=MCCC 1K04072T).

We often use the phrase “Birds of a feather flock together” to describe similar people that spend time together. But, is this true for birds? We find that in a species that lives in social groups individual personalities are more similar to group mates than to non-group mates. We found no similarity between mate pairs in a solitary, monogamous species. This suggests that assortment by personality might be important for life in social groups.

AbstractAntarctic and Southern Ocean environments are facing increasing pressure from multiple threats. The Antarctic Treaty System regularly looks to the Scientific Committee on Antarctic Research (SCAR) for the provision of independent and objective advice based on the best available science to support decision-making, policy development and effective environmental management. The recently approved SCAR Scientific Research Programme Ant-ICON - ‘Integrated Science to Inform Antarctic and Southern Ocean Conservation‘ - facilitates and coordinates high-quality transdisciplinary research to inform the conservation and management of Antarctica, the Southern Ocean and the sub-Antarctic in the context of current and future impacts. The work of Ant-ICON focuses on three research themes examining 1) the current state and future projections of Antarctic systems, species and functions, 2) human impacts and sustainability and 3) socio-ecological approaches to Antarctic and Southern Ocean conservation, and one synthesis theme that seeks to facilitate the provision of timely scientific advice to support effective Antarctic conservation. Research outputs will address the most pressing environmental challenges facing Antarctica and offer high-quality science to policy and advisory bodies including the Antarctic Treaty Consultative Meeting, the Committee for Environmental Protection and the Scientific Committee of the Commission for the Conservation of Antarctic Marine Living Resources.