i-Motif在分子拥挤条件下的性质  

Properties of i-Motif Under Molecular Crowding Conditions

作　　者：周俊[1,2] 贾国卿[1,2] 冯兆池[1] 李灿[1] 

机构地区：[1]中国科学院大连化学物理研究所,催化基础国家重点实验室,大连116023 [2]中国科学院研究生院,北京100049

出　　处：《高等学校化学学报》2010年第2期309-311,共3页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20673110和20621063)资助

摘　　要：i-Motif is formed from two parallel duplexes by intercalating with each other in an antiparallel orientation and each duplex is held together-via-hemiprotonated cytosine+-cytosine base pairs.However,a cell is crowded with various biomolecules and little is known about the properties of i-Motif under molecular crowding conditions until now.In the present study,we used human telomeric DNA sequence,[C3TA23C3,as a model system to investigate such problem by circular dichroism(CD) and UV absorbance spectroscopy.Based on the CD spectra,we found that there were no changes about the structure of i-Motif in the presence of polyethylene glycol(PEG).CD melting results showed that the thermal stability of i-Motif was increased under molecular crowding conditions compare to that in dilute buffer,which was further demonstrated by UV-melting results.This work suggests that molecular crowding could not affect the structure of i-Motif,which may depend on pH,while could enhance the thermal stability of i-Motif.i-Motif is formed from two parallel duplexes by intercalating with each other in an antiparallel orientation and each duplex is held together-via-hemiprotonated cytosine＋-cytosine base pairs.However,a cell is crowded with various biomolecules and little is known about the properties of i-Motif under molecular crowding conditions until now.In the present study,we used human telomeric DNA sequence,[C3TA23C3,as a model system to investigate such problem by circular dichroism（CD） and UV absorbance spectroscopy.Based on the CD spectra,we found that there were no changes about the structure of i-Motif in the presence of polyethylene glycol（PEG）.CD melting results showed that the thermal stability of i-Motif was increased under molecular crowding conditions compare to that in dilute buffer,which was further demonstrated by UV-melting results.This work suggests that molecular crowding could not affect the structure of i-Motif,which may depend on pH,while could enhance the thermal stability of i-Motif.

关 键 词：I-MOTIF 分子拥挤 聚乙二醇 

分 类 号：O643[理学—物理化学]