TOP1 Protein, Human (765a.a, sf9, His)

The TOP1 protein is critical in cellular processes, mitigating DNA supercoiling and torsional tension during replication and transcription. It does this by transiently cutting and rejoining a DNA strand, introducing breaks through transesterification. TOP1 Protein, Human (765a.a, sf9, His) is the recombinant human-derived TOP1 protein, expressed by Sf9 insect cells , with N-His labeled tag. The total length of TOP1 Protein, Human (765a.a, sf9, His) is 765 a.a., with molecular weight of ~93.1 kDa.

TOP1 protein plays a pivotal role in cellular processes by alleviating the supercoiling and torsional tension of DNA generated during DNA replication and transcription. This is achieved through the transient cleavage and subsequent rejoining of one strand of the DNA duplex. The enzyme introduces a single-strand break via transesterification at a specific target site in duplex DNA, leading to the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate. This intermediate expels a 5'-OH DNA strand, allowing the free DNA strand to rotate around the intact phosphodiester bond on the opposing strand, effectively removing DNA supercoils. In the final religation step, the DNA 5'-OH attacks the covalent intermediate, leading to the expulsion of the active-site tyrosine and restoration of the DNA phosphodiester backbone. Beyond its role in DNA topology maintenance, TOP1 is involved in the regulation of alternative splicing, exemplified by its impact on tissue factor (F3) pre-mRNA in endothelial cells. Additionally, it contributes to the circadian transcription of the core circadian clock component BMAL1 by modifying the chromatin structure surrounding the ROR response elements (ROREs) on the BMAL1 promoter.

The enzyme activity of this recombinant protein is testing in progress, we cannot offer a guarantee yet.

Human

Sf9 insect cells

N-His

P11387 (M1-F765)

7150  [NCBI]

Approximately 93.1 kDa

Greater than 95% as determined by reducing SDS-PAGE.

Solution.

Supplied as a 0.2 μm filtered solution of 20 mM Tris, pH 7.5, 200 mM NaCl, 20% Glycerol.

<1 EU/μg, determined by LAL method.

N/A.

Stored at -80°C for 1 year. It is stable at -20°C for 3 months after opening. It is recommended to freeze aliquots at -80°C for extended storage. Avoid repeated freeze-thaw cycles.

Shipping with dry ice.