为了获取具有广泛适用性的DNA聚合酶,将深海热液区获得的超嗜热古菌Palaeococcus pacificus DY20341的Pol B DNA聚合酶和d UTPase进行原核表达和纯化,将得到的Pol B DNA聚合酶及d UTPase混合后用于扩增古菌、细菌和真核生物的基因.通过...为了获取具有广泛适用性的DNA聚合酶,将深海热液区获得的超嗜热古菌Palaeococcus pacificus DY20341的Pol B DNA聚合酶和d UTPase进行原核表达和纯化,将得到的Pol B DNA聚合酶及d UTPase混合后用于扩增古菌、细菌和真核生物的基因.通过PCR反应成功地扩增了商业化Pfu DNA聚合酶所不能扩增的Palaeococcus pacificus DY2034的琼脂酶基因.由此可知,尽管商业化的DNA聚合酶多种多样,针对不同扩增目的片段所需的特异DNA聚合酶体系仍然是必要的,这是又一嗜热古菌B家族DNA聚合酶应用的报道.展开更多
Background: Systemic lupus eiLythenaatosus (SLE) is a prototypic autoimmune disease wida complex genetic inheritance. This study was conducted to examine whether the association ofa proliferation-inducing ligand (...Background: Systemic lupus eiLythenaatosus (SLE) is a prototypic autoimmune disease wida complex genetic inheritance. This study was conducted to examine whether the association ofa proliferation-inducing ligand (APRIL), spermatogenesis associated 8 (SPATA8), platelet-derived growth lhctor receptor-alpha (PDGFRA), and DNA polymerase beta (POLB) with SLE can be replicated in a Chinese Han population. Methods: Chinese SLE patients (n = 1247) and ethnically and geographically matched healthy controls (n 1440) were genotyped for the APRI L, SPATAS. PDGFRA, and POLB single-nucleotide polymorphisms (SN Ps), rs3803800 rs8023715, rs1364089 and rsl2678588 using the Sequenom MassARRAY System. Results: The Chinese Hart SLE patients and controls had statistically similar liequencies of alleles and genotypes of four gene polynlorphisms. Moreover, no association signal was detected on different genetic models (additive, dominant, and recessive, all, P〉 0.05) or in SLE subgroups stratified by various clinical nlanifestations (all, P 〉 0.05). Conclusions: Different genetic backgrounds from different ancestries and various populations may result in different genetic risk litctors for SLE. We did not detect any significant association with SNPs of APRIL SPATAS, PDGFRA, and POLB.展开更多
Euryarchaeota and Crenarchaeota, the two main lineages of the domain Archaea, encode different chromatin proteins and differ in the use of replicative DNA polymerases. Crenarchaea possess a single family B DNA polymer...Euryarchaeota and Crenarchaeota, the two main lineages of the domain Archaea, encode different chromatin proteins and differ in the use of replicative DNA polymerases. Crenarchaea possess a single family B DNA polymerase(Pol B), which is capable of strand displacement modulated by the chromatin proteins Cren7 and Sul7 d. Euryarchaea have two distinct replicative DNA polymerases, PolB and PolD, a family D DNA polymerase. Here we characterized the strand displacement activities of Pol B and Pol D from the hyperthermophilic euryarchaeon Pyrococcus furiosus and investigated the influence of HPf A1, a homolog of eukaryotic histones from P. furiosus, on these activities. We showed that both Pol B and Pol D were efficient in strand displacement. HPf A1 inhibited DNA strand displacement by both DNA polymerases but exhibited little effect on the displacement of a RNA strand annealed to single-stranded template DNA. This is consistent with the finding that HPf A1 bound more tightly to double-stranded DNA than to a RNA:DNA hybrid. Our results suggest that, although crenarchaea and euryarchaea differ in chromosomal packaging, they share similar mechanisms in modulating strand displacement by DNA polymerases during lagging strand DNA synthesis.展开更多
基金the grant from the National Natural Science Foundation of China
文摘Background: Systemic lupus eiLythenaatosus (SLE) is a prototypic autoimmune disease wida complex genetic inheritance. This study was conducted to examine whether the association ofa proliferation-inducing ligand (APRIL), spermatogenesis associated 8 (SPATA8), platelet-derived growth lhctor receptor-alpha (PDGFRA), and DNA polymerase beta (POLB) with SLE can be replicated in a Chinese Han population. Methods: Chinese SLE patients (n = 1247) and ethnically and geographically matched healthy controls (n 1440) were genotyped for the APRI L, SPATAS. PDGFRA, and POLB single-nucleotide polymorphisms (SN Ps), rs3803800 rs8023715, rs1364089 and rsl2678588 using the Sequenom MassARRAY System. Results: The Chinese Hart SLE patients and controls had statistically similar liequencies of alleles and genotypes of four gene polynlorphisms. Moreover, no association signal was detected on different genetic models (additive, dominant, and recessive, all, P〉 0.05) or in SLE subgroups stratified by various clinical nlanifestations (all, P 〉 0.05). Conclusions: Different genetic backgrounds from different ancestries and various populations may result in different genetic risk litctors for SLE. We did not detect any significant association with SNPs of APRIL SPATAS, PDGFRA, and POLB.
基金supported by the National Natural Science Foundation of China (31130003, 30921065)
文摘Euryarchaeota and Crenarchaeota, the two main lineages of the domain Archaea, encode different chromatin proteins and differ in the use of replicative DNA polymerases. Crenarchaea possess a single family B DNA polymerase(Pol B), which is capable of strand displacement modulated by the chromatin proteins Cren7 and Sul7 d. Euryarchaea have two distinct replicative DNA polymerases, PolB and PolD, a family D DNA polymerase. Here we characterized the strand displacement activities of Pol B and Pol D from the hyperthermophilic euryarchaeon Pyrococcus furiosus and investigated the influence of HPf A1, a homolog of eukaryotic histones from P. furiosus, on these activities. We showed that both Pol B and Pol D were efficient in strand displacement. HPf A1 inhibited DNA strand displacement by both DNA polymerases but exhibited little effect on the displacement of a RNA strand annealed to single-stranded template DNA. This is consistent with the finding that HPf A1 bound more tightly to double-stranded DNA than to a RNA:DNA hybrid. Our results suggest that, although crenarchaea and euryarchaea differ in chromosomal packaging, they share similar mechanisms in modulating strand displacement by DNA polymerases during lagging strand DNA synthesis.