激光生物学报
激光生物學報
격광생물학보
ACTA LASER BIOLOGY SINICA
2001年
1期
1-6
,共6页
曹恩华%陈艾%张晓嫣%孙雪光%秦静芬%刘大格%白春礼
曹恩華%陳艾%張曉嫣%孫雪光%秦靜芬%劉大格%白春禮
조은화%진애%장효언%손설광%진정분%류대격%백춘례
补骨脂素%HeLa细胞%端粒DNA%T-loop%原子力显微镜
補骨脂素%HeLa細胞%耑粒DNA%T-loop%原子力顯微鏡
보골지소%HeLa세포%단립DNA%T-loop%원자력현미경
HeLa细胞DNA，经Rsal(1?250?U)和HinF1(1250U)内切酶酶解、Bio-gelP-2柱分离，得到端粒DNA。原子力显微镜(AFM)的直接观测结果表明在UVA照射下，补骨脂素可结合到端粒DNA的特殊位置，其光交链产物随照射时间增长而增加。与此同时，P53表达和端粒酶活性发生变化。纯化的端粒DNA片段在AFM下呈带尾的T-环结构(T-loop)。按其高度判断T-环部分为双链DNA结构，T-环与尾部交接处具有三链或四链结构特征。
HeLa細胞DNA，經Rsal(1?250?U)和HinF1(1250U)內切酶酶解、Bio-gelP-2柱分離，得到耑粒DNA。原子力顯微鏡(AFM)的直接觀測結果錶明在UVA照射下，補骨脂素可結閤到耑粒DNA的特殊位置，其光交鏈產物隨照射時間增長而增加。與此同時，P53錶達和耑粒酶活性髮生變化。純化的耑粒DNA片段在AFM下呈帶尾的T-環結構(T-loop)。按其高度判斷T-環部分為雙鏈DNA結構，T-環與尾部交接處具有三鏈或四鏈結構特徵。
HeLa세포DNA，경Rsal(1?250?U)화HinF1(1250U)내절매매해、Bio-gelP-2주분리，득도단립DNA。원자력현미경(AFM)적직접관측결과표명재UVA조사하，보골지소가결합도단립DNA적특수위치，기광교련산물수조사시간증장이증가。여차동시，P53표체화단립매활성발생변화。순화적단립DNA편단재AFM하정대미적T-배결구(T-loop)。안기고도판단T-배부분위쌍련DNA결구，T-배여미부교접처구유삼련혹사련결구특정。
DNA from HeLa cells was cleaved with Rasl and Hinf ,and thenpurified by Bio-Gel P-2 column.Results showed that upon near-UV-irradiation,psoralen coul d be targeted to the repetitive sequences of telomeres and the psoralen cross-li nking products increased with increase of irradiation time.At same time,the chan ges of the expression o f P53 oncogene and telomerase was were observed. Large duplex loops (T-loop) wit h a tail were observed directly by AFM.The loop-tail junction position was assu m ed to be a tri-or tetra- strand DNA structure according to its apparent height.
