Molecular cloning, characterization and expression analysis of Tim-3 and Galectin-9 in the woodchuck model

Comparative Analysis of Gut Microbiomes in Laboratory Chinchillas, Ferrets, and Marmots: Implications for Pathogen Infection Research

Gut microbes play a vital role in the health and disease of animals, especially in relation to pathogen infections. Chinchillas, ferrets, and marmots are commonly used as important laboratory animals for infectious disease research. Here, we studied the bacterial and fungal microbiota and discovered that chinchillas had higher alpha diversity and a higher abundance of bacteria compared to marmots and ferrets by using the metabarcoding of 16S rRNA genes and ITS2, coupled with co-occurrence network analysis. The dominant microbes varied significantly among the three animal species, particularly in the gut mycobiota. In the ferrets, the feces were dominated by yeast such as Rhodotorula and Kurtzmaniella, while in the chinchillas, we found Teunomyces and Penicillium dominating, and Acaulium, Piromyces, and Kernia in the marmots. Nevertheless, the dominant bacterial genera shared some similarities, such as Clostridium and Pseudomonas across the three animal species. However, there were significant differences observed, such as Vagococcus and Ignatzschineria in the ferrets, Acinetobacter and Bacteroides in the chinchillas, and Bacteroides and Cellvibrio in the marmots. Additionally, our differential analysis revealed significant differences in classification levels among the three different animal species, as well as variations in feeding habitats that resulted in distinct contributions from the host microbiome. Therefore, our data are valuable for monitoring and evaluating the impacts of the microbiome, as well as considering potential applications.

The Genome Sequence of the Eastern Woodchuck (Marmota monax) - A Preclinical Animal Model for Chronic Hepatitis B

The Eastern woodchuck (Marmota monax) has been extensively used in research of chronic hepatitis B and liver cancer because its infection with the woodchuck hepatitis virus closely resembles a human hepatitis B virus infection. Development of novel immunotherapeutic approaches requires genetic information on immune pathway genes in this animal model. The woodchuck genome was assembled with a combination of high-coverage whole-genome shotgun sequencing of Illumina paired-end, mate-pair libraries and fosmid pool sequencing. The result is a 2.63 Gigabase (Gb) assembly with a contig N50 of 74.5 kilobases (kb), scaffold N50 of 892 kb, and genome completeness of 99.2%. RNA sequencing (RNA-seq) from seven different tissues aided in the annotation of 30,873 protein-coding genes, which in turn encode 41,826 unique protein products. More than 90% of the genes have been functionally annotated, with 82% of them containing open reading frames. This genome sequence and its annotation will enable further research in chronic hepatitis B and hepatocellular carcinoma and contribute to the understanding of immunological responses in the woodchuck.

Identification, characterization, expression profiles of OlHavcr2 in medaka (Oryzias latipes)

Hepatitis A virus cellular receptor2 (Havcr2) also named T-cell immunoglobulin and mucin domain containing-3 (Tim-3) was initially described as a T helper 1-specific cell surface protein, a member of Tim family implicated in the regulating process of adaptive and innate immune responses. Here, medaka (Oryzias latipes) Havcr2 (OlHavcr2) was isolated and characterized. Unlike other Havcr2 proteins, OlHavcr2 possesses two Ig-like domains but lacks cytoplasmic and transmembrane domains. RT-PCR results revealed that OlHavcr2 mRNA was expressed strongly in the liver, moderately in the intestine, heart and ovary, and weakly in the muscle, gill, brain, eye, spleen, and testis. OlHavcr2 expression begun from gastrula stage and was maintained until hatching. The signal of OlHavcr2 was mainly identified in the blood system in the yolk sac by in situ hybridization. These results indicated that OlHavcr2 is expressed ubiquitously in adult tissues, and is a zygotic gene expressed from gastrula onwards in embryogenesis. OlHavcr2 may play a significant role in the blood system of medaka. In the immune organs, OlHavcr2 expression was affected by the immune stimulants, lipopolysaccharide and poly I:C, suggesting that OlHavcr2 was involved in innate immunity and adaptive immunity in medaka.