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Background: Gossypium raimondii is a Verticillium wilt-resistant cotton species whose genome encodes numerous disease resistance genes that play important roles in the defence against pathogens. However, the characteristics of resistance gene analogues (RGAs) and Verticillium dahliae response loci (VdRLs) have not been investigated on a global scale. In this study, the characteristics of RGA genes were systematically analysed using bioinformatics-driven methods. Moreover, the potential VdRLs involved in the defence response to Verticillium wilt were identified by RNA-seq and correlations with known resistance QTLs. Results: The G. raimondii genome encodes 1004 RGA genes, and most of these genes cluster in homology groups based on high levels of similarity. Interestingly, nearly half of the RGA genes occurred in 26 RGA-gene-rich clusters (Rgrcs). The homology analysis showed that sequence exchanges and tandem duplications frequently occurred within Rgrcs, and segmental duplications took place among the different Rgrcs. An RNA-seq analysis showed that the RGA genes play roles in cotton defence responses, forming 26 VdRLs inside in the Rgrcs after being inoculated with V. dahliae. A correlation analysis found that 12 VdRLs were adjacent to the known Verticillium wilt resistance QTLs, and that 5 were rich in NB-ARC domain-containing disease resistance genes. Conclusions: The cotton genome contains numerous RGA genes, and nearly half of them are located in clusters, which evolved by sequence exchanges, tandem duplications and segmental duplications. In the Rgrcs, 26 loci were induced by the V. dahliae inoculation, and 12 are in the vicinity of known Verticillium wilt resistance QTLs. [ABSTRACT FROM AUTHOR]

Background: Hepatitis B virus (HBV) infection causes large amount of unfolding or false-folding protein accumulation in the endoplasmic reticulum (ER), which in turn induces the expression of glucose-regulated protein 78 (GRP78). The aim in the present study was to analyse the potential association between GRP78 single-nucleotide polymorphisms (SNPs) and the risk of HBV infection. Methods: The associations between seven common GRP78 polymorphisms in the promoter (rs391957, rs17840762, rs17840761, rs11355458) and in the 3' untranslated region (UTR) (rs16927997, rs1140763, rs12009) and possible risk of chronic HBV infection were assessed in a case-control study. 496 cases and 539 individually matched healthy controls were genotyped. Results: Overall, no associations were observed in genotypic analyses. In addition, haplotypes and diplotypes combining those SNPs in the promoter or in the 3' UTR in high linkage disequilibrium (LD) were also not associated with HBV risk. Conclusion: These observations do not support a role for GRP78 polymorphisms in HBV infection in a predominantly Chinese Han population. [ABSTRACT FROM AUTHOR]