Molecular biology applications of the red king crab duplex-specific nuclease

Duplex-specific nuclease (DSN) from hepatopancreas of the craboid Paralithodes camtschaticus (red king crab) has a unique combination of properties. Along with thermal stability and a high optimal temperature of catalysis, this enzyme exhibits high substrate selectivity, cleaving only DNA in duplexes (DNA-DNA or DNA-RNA). Accordingly, it digests neither single strands (nor single-stranded regions) of DNA, nor RNA strands with any secondary structure. Such properties make it possible to create unique protocols based on DSN, which is also an important object of fundamental research in the field of nuclease evolution. The review considers diverse applications of the red king crab DSN in modern methods of molecular biology.

Association of cytokine gene polymorphisms with the complications of allogeneic haematopoietic stem cell transplantation

The purpose of our study was to confirm the prevalence of the association between single nucleotide polymorphisms present in genes encoding cytokines and the complications occurring after haematopoietic stem cell transplantation (HSCT). 108 recipients and 81 donors were typed for TNF-α (-308), TGF-β1 (codon 10, 25), IL-10 (-1082, -819, -592), IL-6 (-174) and INF-γ (+874). Our studies have shown a tendency toward association between the occurrence of acute form of graft versus host disease (aGVHD) and IL-6 genotype. Homozygote C/C was less likely to develop aGVHD (p=0,09). Genotype GCC/ATA in IL-10 recipient gene alone had protective effect against the occurrence of aGVHD (p=0,01). Furthermore, GCC/ATA protected the host against developing the disease in the clinically relevant grades (II-IV) (p=0,03). In addition, the recipient's T/T G/G genotype (TGF-β1) predisposed to the development of both acute (p=0,06 - trend) and chronic (p=0,04) GVHD and also severe aGVHD (p=0,004). We also observed a statistically significant association between the genotype of recipient and the risk of infection - the protective function of the G/C IL-6 in the bloodstream infections (p=0,001). Our results suggest that IL-6, IL-10 and TGF-β1 genotypes of recipient are the most associated with the risk of complications after HSCT.

Association Between Interleukin-6 -572 C>G and -174 G>C Polymorphisms and Hypertension: A Meta-analysis of Case-control Studies

Whether hypertension is associated with -572 C>G or -174 G>C polymorphism in interleukin (IL)-6 genes still remains hazy and ambiguous.We conducted a meta-analysis to offer a more reliable and clearer evaluation about the association.Electronic literature databases including PubMed, Web of Science, EMBASE, Google Scholar, Chinese National Knowledge Infrastructure and Wanfang database were searched.The study included the following: evaluating associations between -572 C>G or -174 G>C polymorphism in IL-6 gene and hypertension; case-control design; essential information must be offered; precise diagnostic criteria of hypertension; and no language restriction.Patients who met the diagnostic criteria and controls without a history of hypertension were included. Interventions were not available.A quality assessment was conducted using Newcastle-Ottawa scale. Combined odds ratios with 95% confidence intervals were calculated in 5 genetic models. Sources of heterogeneity were explored by subgroup analysis, meta-regression, and Galbraith plots. Finally, test for publication bias was performed to prove the stabilization.Fifteen studies were finally included. Eleven articles were judged high-quality reports. Overall, the -572 C>G polymorphism was proved to be significantly associated with hypertension in 4 genetic models. Subgroup analysis based on ethnicity revealed significant associations in Asian population in recessive model and homozygote comparison. The association in Europeans and Mid-East required further confirmation. No significant association was observed between the -174 G>C polymorphism and hypertension under all of the genetic models.The limitations of the study were the following: restrictive number of eligible studies limited the extrapolation range in subgroup analysis; gene-environment factors could not be described due to lack of data; some relevant studies could not be included because of various reasons.Current researches supported the association between the development of hypertension and the -572 C>G rather than -174 G>C polymorphism. Future well designed epidemiological studies may evaluate the possible gene-environment interactions.

Role of the promoter polymorphism IL-6 -174G/C in dermatomyositis and systemic lupus erythematosus

The promoter polymorphism -174G/C within the interleukin-6 gene (IL-6) has been reported to have a functional importance through the modulation of IL-6 gene expression in vitro and in vivo. IL-6 is thought to play an important role in autoimmune diseases and the effect of its receptor inhibitor-tocilizumab-has been recently studied. The aim of this case-control study was to investigate the association between the interleukin-6 -174G/C single nucleotide polymorphism and the susceptibility to dermatomyositis (DM) and systemic lupus erythematosus (SLE) in Bulgarian patients. Altogether, 87 patients-52 with SLE and 35 with DM-as well as 80 unrelated healthy controls were included in this study. All of them were analyzed by restriction fragment length polymorphism analysis (RFLP). The GG genotype and the G allele appeared to be associated with SLE, especially in women. None of the genotypes showed an association with DM. However, the G allele appeared to be associated with muscle weakness and it is a risk factor for elevated muscle enzymes. Our results indicate that IL-6 -174G/C polymorphism might be associated with the susceptibility to SLE especially in women. Although it is not associated with DM, it seems that IL-6 -174G/C polymorphism could modulate some clinical features in the autoimmune myopathies.