Morphological Variation of Higher Order Structure of Long Duplex DNA and its genetic activity

长双链DNA高阶结构的形态变异及其遗传活性

• 批准号: 11837019
• 负责人: YOSHIKAWA Yuko
• 金额: $ 1.92万
• 依托单位: College of Nagoya Bunri University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11837019/
• 关键词: long duplex DNA; higher order structure; fluorescence microscopy; histone H1; laser manipulation; レーザー; ヒストンH1

Compaction of DNA is a common feature in native genomes, e.g., in chromatin or phage heads. The manner of packaging is expected to play an essential role in the biological functions of DNA, such as replication and transcription.I have made direct observations on the conformational change of individual long duplex DNA molecules using fluorescence microscopy. It has been shown that giant DNAs exhibits an all-or-none change, or switching, in the folding transition. I have also reported that complexes of DNA-histone HI form a pearl necklace-like structure when the complexes were prepared by a natural dilution from a high salt solution to a low salt solution. In addition, we have applied laser-tweezers to manipulate the DNA-histone H1 under the real time observation with fluorescence microscopy. When the DNA-H1 complex is optically transported from a low-salt solution to a high-salt solution, its conformation changes from a compact to an elongated structure. With the reverse procedure, the elongated chain shrinks into a compact state. Laser manipulation is expected to be a powerful tool for research on the dynamics of various biomolecules mimicking intracellular processes.

DNA的压实是天然基因组的共同特征，例如在染色质或噬菌体头中。包装的方式预计在DNA的生物学功能中发挥重要作用，如复制和转录。我用荧光显微镜对单个长双链DNA分子的构象变化进行了直接观察。已经证明，巨型dna在折叠转变中表现出全有或全无的变化或切换。我也报道过dna -组蛋白HI复合物从高盐溶液自然稀释到低盐溶液时形成珍珠项链状结构。此外，我们还利用激光镊子对dna -组蛋白H1进行了操作，并在荧光显微镜下实时观察。当DNA-H1复合体从低盐溶液光学运输到高盐溶液时，其构象从紧凑结构变为细长结构。通过相反的过程，拉长的链条收缩成紧致的状态。激光操作有望成为模拟细胞内过程的各种生物分子动力学研究的有力工具。

项目成果

Yuko Yoshikawa: "Formation of a Giant Toroid from Long Duplex DNA"Langmuir. 15. 4085-4088 (1999)

Yuko Yoshikawa：“从长双链 DNA 形成巨型环形线圈”Langmuir。

Kenichi Yoshikwa: "All-or-none folding transition in giant mammalian DNA"Chem.Phys.Lett.. (印刷中). (2002)

Kenichi Yoshikwa：“巨型哺乳动物 DNA 中的全或无折叠转变”Chem.Phys.Lett..（出版中）。

Yuko Yoshikawa: "Light illumination induces large change in the higher order structure of giant DNAs complexed with maltosylated amino-pendant polyethylene glycol and sodium dodecyl sulfate"Polym.J.. 31. 1025-1028 (1999)

Yuko Yoshikawa：“光照诱导与麦芽糖化氨基侧链聚乙二醇和十二烷基硫酸钠复合的巨型 DNA 的高级结构发生巨大变化”Polym.J. 31. 1025-1028 (1999)

Y, Yoshikawa, K, Yoshikawa and T, Kanbe: "Formation of a Giant Toroid from Long"Langmuir. 15. 4085-4088 (1999)

Y，Yoshikawa，K，Yoshikawa 和 T，Kanbe：“从朗缪尔形成巨型环形线圈”。

Y, Yoshikawa, S, M, Nomura, T, Kanbe and K, Yoshikawa: "Controlling the Folding/Unfolding Transition of DNA-Histone H1 Complex by Direct Optical Manipulation"Chem. Phys. Lett.. 330. 77-82 (2000)

Y，Yoshikawa，S，M，Nomura，T，Kanbe 和 K，Yoshikawa：“通过直接光学操作控制 DNA-组蛋白 H1 复合物的折叠/解折叠转变”Chem。