Type I interferon receptors in goose: Molecular cloning, structural identification, evolutionary analysis and age-related tissue expression profile

Cloning and characterisation of type I interferon receptor 1 in orange-spotted grouper (Epinephelus coioides) for response to nodavirus infection

Grouper is known as a highly economical teleost species in the Asian aquaculture industry; however, intensive culture activities easily cause disease outbreak, especially viral disease. For the prevention of viral outbreaks, interferon (IFN) is among the major defence systems being studied in different species. Fish type I IFNs are known to possess antiviral properties similar to mammalian type I IFNs. In order to stimulate antiviral function, IFN will bind to its cognate receptor, the type I interferon receptor (IFNAR), composed of heterodimeric receptor subunits known as IFNAR1 and IFNΑR2. The binding of type I interferon to receptors assists in the transduction of signals from the external to internal environments of cells to activate biological responses. In order to study the function of IFN, we first need to understand IFN receptors. In this study, we cloned and identified IFNAR1 in orange-spotted grouper (osgIFNAR1) and noted the up-regulated mRNA expression of the receptor and downstream effectors in the head kidney cells with cytokine treatment. The transcriptional expression of osgIFNAR1, which is characterised using polyinosinic-polycytidylic acid (poly[I:C]) and lipopolysaccharide (LPS) treatments, indicated the involvement of osgIFNAR1 in the immune response of grouper. The subcellular localisation of osgIFNAR1 demonstrated scattering across the grouper cell. Viral infection showed the negative feedback regulation of osgIFNAR1 in grouper larvae. Further loss of function of IFNAR1 showed a decreased expression of the virus. This study reported the identification of osgIFNAR1 and characterisation of receptor sensitivity towards immunostimulants, cytokine response, and viral challenge in the interferon pathway of orange-spotted grouper and possible different role of the receptor in viral production. Together, these results provide a frontline report of the potential function of osgIFNAR1 in the innate immunity of teleost.

Molecular identification and comparative transcriptional analysis of myxovirus resistance GTPase (Mx) gene in goose (Anser cygnoide) after H9N2 AIV infection

Interferon (IFN)-induced myxovirus resistance (Mx) GTPases belong to the family of dynamin-like GTPases and control a diverse range of viruses. In this study, the identified goose Mx (goMx) mRNA is 2009bp long, shares partially conserved exons with other homologues, and shares highly conserved domains in its primary structure. The amino acid position 629 (629aa) of the goMx protein was identified as serine (Ser), in contrast to the Ser located at 631aa in chicken Mx, which is considered to be responsible for the lack of chicken Mx antiviral activity. In addition, the goMx 142aa residue in the dynamin family signature differs from that of other functional Mx proteins. Transcriptional analysis revealed that goMx was mainly expressed in the digestive, respiratory and immune systems in an age-specific manner. GoMx transcript levels in goose peripheral blood mononuclear cells (PBMCs) were found to be significantly up-regulated by various agonists and avian viruses. Furthermore, a time course study of the effects of H9N2 avian influenza virus (AIV) on goMx expression in infected goslings suggested that H9N2 AIV affected goMx expression. However, significant changes in goMx expression were observed in the trachea, lung and small intestine of infected birds. Altogether, these results indicate that goMx protein may have acquired its broad antiviral activity by changing only a few amino acids at select sites, even as it shares a conserved architectures with species.

Screening of intracerebral hemorrhage associated allele combinations at different loci using a novel association analysis

BACKGROUND

Genetic research has progressed along with scientific and technological developments. However, it is difficult to identify frequency differences in the allele combination at cross-loci.

OBJECTIVE

The purpose of this study was to examine the relationship between the presence of specific allele combinations of short tandem repeat (STR) loci and the onset of intracerebral hemorrhage (ICH) using a novel methodology.

METHODS

DNA samples were collected from patients with ICH, who were adult population. There were a total of 51 Chinese patients (102 chromosomes), comprising 30 males and 21 females. Alleles from short tandem repeat (STR) loci were determined using the STR Profiler Plus PCR amplification kit (15 STR loci). Statistically significant differences between observed and expected frequencies of allele combinations were identified. To further determine allele combinations related to the disease, analyses of patient age at disease onset for those carrying a specific allele combination were conducted. Finally, cross-validation of the two sets of analytical results was carried out.

RESULTS

A total of 1550 pairwise combinations were obtained by computer counting, of which eight pairs of alleles showed significant differences between the observed and expected frequencies (p<0.05, from 0.006 to 0.042). The p value for the cross-validation analysis was less than 0.05 for two pairs of alleles (D13S317-11 and vWA-17, p=0.021; D7S820-13 and D2S1338-18, p=0.023).

CONCLUSIONS

The study identified each population had a unique gene distribution and that distribution followed certain rules. ICH onset may be associated with this allele combinations (D13S317-11 and vWA-17; D7S820-13 and D2S1338-18). The new methodology used in this study could enable additional discoveries pertaining to the relationship between specific allele combinations at different loci and the onset of complex diseases.