Synthesis of 4-Thiothymine Based Photolabels as New Tools for Nucleic Acids Structural Studies in Solution: Formation of Long-Range Photo-Cross-Links within a Hammerhead Ribozyme Domain
作者:Carole Saintomé、Pascale Clivio、Jean-Louis Fourrey、Anne Woisard、Philippe Laugâa、Alain Favre
DOI:10.1016/s0040-4020(00)00024-7
日期:2000.2
The nucleosidic photolabels 2–5, able to form long-range photo-cross-links, have been used to further investigate the tertiary folding of a hammerhead ribozyme domain. These photolabels derive from 2′-deoxyuridine which is substituted at its C-5 position with a photoactivable 4-thiothymine unit linked by a chain of various length and rigidity. Derivatives 2–5 were inserted at strategic positions of
所述核苷photolabels 2 - 5,能够形成远距离光交联,已经使用以进一步调查锤头状核酶结构域的三级折叠。这些光标记物衍生自2'-脱氧尿苷,其在其C-5位置被可光活化的4-硫代胸腺嘧啶单元取代,该单元通过各种长度和刚性的链连接。衍生物2 - 5分别以deoxysubstrate类似物(的战略位置插入德尚锤头状核酶(的)RZ)。共价交联是通过在裂解条件下组装的Rz - dS络合物的366 nm辐照产生的。该保证金不映射涉及这些交联的残基以给出新的邻近数据集,扩展了先前通过使用2'-deoxy-4-thiouridine 1进行固有光标记获得的那些。因此,与零长交联剂1,photolabels 2 - 5显示出其严重依赖于接头的长度和柔性和其掺入的位点较高的勘探容量。有趣的是,与1相反,这些光标记物能够交联涉及双G的残基:错配以及相邻碱基对的残基。这些发现表明错配结构域在溶液中表现出意想不到的构象灵活性。