This research presented an annealing strategy to identify hairpin DNA from coil DNA with the same base composition but different arrangements using electrospray mass spectrometry（ESI-MS）.A series of single-stranded ...This research presented an annealing strategy to identify hairpin DNA from coil DNA with the same base composition but different arrangements using electrospray mass spectrometry（ESI-MS）.A series of single-stranded DNA were annealed with their complementary sequences,respectively.All the five pairs of hairpin DNA and coil DNA were unambiguously distinguished by ESIMS with annealing strategy.This research offers a potential method to probe the DNA structure by comparing with mass spectral characteristics.展开更多
The technical feasibility of monitoring DNA melting and cooling transitions using a microcantilever substrate has been demonstrated and these results were compared with those measured in solution by circular dichroism...The technical feasibility of monitoring DNA melting and cooling transitions using a microcantilever substrate has been demonstrated and these results were compared with those measured in solution by circular dichroism. DNA hairpins have been immobilized on the surface of gold-coated microcantilever surfaces and their DNA melting and cooling transitions were monitored by nanomechanical deflections. The hairpins comprised of a 16 base-pair GACA repeat motif stem duplex with a 29 nucleotide variable region. Microcantilever deflection profiles, measured by the microcantilever response as a function of temperature, were unique to different hairpins indicative of the molecules’ general stability and denaturation characteristics. The major melting and cooling transition temperatures for all three immobilized oligonucleotides were between 41。C - 52。C. The composition and flexibility of the DNA stem loops were shown to influence the thermal transitions.展开更多
基金Project supported by the National Natural Science Foundation of China(No.90913004) the 973 Program (No.2012CB720600)
文摘This research presented an annealing strategy to identify hairpin DNA from coil DNA with the same base composition but different arrangements using electrospray mass spectrometry（ESI-MS）.A series of single-stranded DNA were annealed with their complementary sequences,respectively.All the five pairs of hairpin DNA and coil DNA were unambiguously distinguished by ESIMS with annealing strategy.This research offers a potential method to probe the DNA structure by comparing with mass spectral characteristics.
文摘The technical feasibility of monitoring DNA melting and cooling transitions using a microcantilever substrate has been demonstrated and these results were compared with those measured in solution by circular dichroism. DNA hairpins have been immobilized on the surface of gold-coated microcantilever surfaces and their DNA melting and cooling transitions were monitored by nanomechanical deflections. The hairpins comprised of a 16 base-pair GACA repeat motif stem duplex with a 29 nucleotide variable region. Microcantilever deflection profiles, measured by the microcantilever response as a function of temperature, were unique to different hairpins indicative of the molecules’ general stability and denaturation characteristics. The major melting and cooling transition temperatures for all three immobilized oligonucleotides were between 41。C - 52。C. The composition and flexibility of the DNA stem loops were shown to influence the thermal transitions.
文摘螺旋-发夹-螺旋DNA糖基化酶超基因家族(helix-hairpin-helix DNA glycosylases superfamily,HhH-DGS)是DNA碱基切除修复(base excision repair, BER)的关键酶之一,在保持基因组的稳定中发挥着重要作用。本研究分析了大麦(Hordeum vulgare L.) HhH-DGS基因家族的分子特征、系统发育、组织表达模式并探究了该基因家族对辐射的响应规律。在大麦基因组的6条染色体上共鉴定到15个HhH-DGS基因,系统发育将其分为9个亚群。不同亚族间HhH-DGS基因外显子数量变异很大,为2~12个。种间与种内共线性分析表明,该基因家族存在于单子叶与双子叶分化前,在大麦基因组内没有发生大规模扩增。HhH-DGS基因启动子含有大量的光调节因子。大麦萌发期的茎基部及花前期的顶端组织中HhH-DGS基因表达量显著高于其他组织器官;HhH-DGS基因HORVU.MOREX.r3.7HG0667530、HORVU.MOREX.r3.3HG0221280、HORVU.MOREX.r3.3HG0223220和HORVU.MOREX.r3.6HG0561680在大麦不同的器官中稳定表达,并在4种辐射处理后表达都上调。HORVU.MOREX.r3.5HG0469860、HORVU.MOREX.r3.7HG0634400和HORVU.MOREX.r3.1HG0074440表现出特异辐射方式响应模式。本研究在解析大麦HhH-DGS基因家族的特征、进化与功能的基础上,为大麦辐射育种提供了参考。
