产品说明
生化/生理作用
Human DNA topoisomerase I is the best studied of the DNA topoisomerase family. It catalyzes the relaxation of both positive and negative supercoiled DNAs without the requirement of energy. In addition to DNA replication and transcriptional activation, DNA topoisomerase I also plays a major role in pre-mRNA splicing, cell cycle and other gene regulatory pathways during cell growth and development. Tyrosine 723 was identified as an active site for the DNA binding activity of DNA topoisomerase I. The covalent intermediate of topo I and DNA complex includes nucleophilic attack by the O4-oxygen of tyrosine 723 on a phosphester linkage in the DNA. Mutation from tyrosine to phenylalanine at position 723 preferentially binds the supercoiled DNA rather than relaxed DNA in the mixture of supercoiled and relaxed DNAs. But mutation at tyr723 neither affects its kinase activity that phosphorylates splicing factors of SR protein family nor its transcription activity of class II genes in vitro.
外形
Clear and colorless frozen liquid solution
制备说明
Use a manual defrost freezer and avoid repeated freeze-thaw cycles. While working, please keep sample on ice.
基本信息
NACRES | NA.26 |
产品性质
生物来源 | human |
重组 | expressed in insect cells |
测定 | ≥80% (SDS-PAGE) |
形式 | frozen liquid |
分子量 | ~92.4 kDa |
包装 | pkg of 5 μg |
储存条件 | avoid repeated freeze/thaw cycles |
浓度 | 1000 μg/mL |
颜色 | clear colorless |
NCBI登记号 | NM_003286 |
UniProt登记号 | P11387 |
运输 | dry ice |
储存温度 | −70℃ |
Gene Information | human ... TOP1(7150) |
安全信息
储存分类代码 | 10 - Combustible liquids |
WGK | WGK 1 |
闪点(F) | Not applicable |
闪点(C) | Not applicable |
Sigma-Aldrich