推荐产品
生物源
human
重組細胞
expressed in insect cells
化驗
≥80% (SDS-PAGE)
形狀
frozen liquid
分子量
~92.4 kDa
包裝
pkg of 5 μg
儲存條件
avoid repeated freeze/thaw cycles
濃度
1000 μg/mL
顏色
clear colorless
NCBI登錄號
UniProt登錄號
運輸包裝
dry ice
儲存溫度
−70°C
基因資訊
human ... TOP1(7150)
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.
外觀
Clear and colorless frozen liquid solution
準備報告
Use a manual defrost freezer and avoid repeated freeze-thaw cycles. While working, please keep sample on ice.
儲存類別代碼
10 - Combustible liquids
水污染物質分類（WGK）
WGK 1
閃點（°F）
Not applicable
閃點（°C）
Not applicable
J J Champoux
The Journal of biological chemistry, 256(10), 4805-4809 (1981-05-25)
Conditions which result in DNA strand breakage by the rat liver DNA nicking-closing enzyme lead to the covalent attachment of the 3'-end of the broken strand to the enzyme. Treatment of this complex with pancreatic DNase leaves a residue of
DNA topoisomerase poisons as antitumor drugs.
L F Liu
Annual review of biochemistry, 58, 351-375 (1989-01-01)
J J Champoux
Annual review of biochemistry, 70, 369-413 (2001-06-08)
DNA topoisomerases solve the topological problems associated with DNA replication, transcription, recombination, and chromatin remodeling by introducing temporary single- or double-strand breaks in the DNA. In addition, these enzymes fine-tune the steady-state level of DNA supercoiling both to facilitate protein
我们的科学家团队拥有各种研究领域经验，包括生命科学、材料科学、化学合成、色谱、分析及许多其他领域.
联系技术服务部门