CDK9-CCNK Heterodimer Protein, Human (Active, sf9, GST, FLAG)

The CDK9 protein plays a central role in transcriptional regulation, promoting the transition from ineffective to efficient elongation by phosphorylating POLR2A, SUPT5H, and RDBP. As part of the CDK9/cyclin-T complex, it participates in phosphorylation events affecting EP300, MYOD1, RPB1/POLR2A, AR, DSIF, and NELFE. CDK9-CCNK Heterodimer Protein, Human (sf9, GST, FLAG) is a recombinant protein dimer complex containing human-derived CDK9-CCNK Heterodimer protein, expressed by sf9 insect cells , with N-Flag, N-GST labeled tag.

The CDK9ic protein emerges as a central player in the intricate regulation of transcription, orchestrating a diverse range of cellular processes. As a pivotal member of the cyclin-dependent kinase pair (CDK9/cyclin-T) complex, also known as positive transcription elongation factor b (P-TEFb), it facilitates the transition from abortive to productive elongation by phosphorylating the C-terminal domain (CTD) of the large subunit of RNA polymerase II (POLR2A), SUPT5H, and RDBP. This complex, inactive in the 7SK small nuclear ribonucleoprotein (snRNP) complex form, engages in phosphorylation events targeting EP300, MYOD1, RPB1/POLR2A, AR, and the negative elongation factors DSIF and NELFE. Beyond its role in transcription, CDK9-CCNK regulates cytokine-inducible transcription networks, promoting RNA synthesis in genetic programs for cell growth, differentiation, and viral pathogenesis. The complex also plays a critical role in cotranscriptional histone modification, mRNA processing, mRNA export, and a network of chromatin modifications. Moreover, it contributes to genome integrity maintenance, replication stress response, and cardiac myocyte enlargement. The multifaceted activities of CDK9-CCNK underscore its significance in governing diverse cellular functions and molecular pathways.

The activity was measured by off-chip mobility shift assay(MSA). The enzyme was incubated with fluorecence-labeled substrate and Mg(or Mn)/ATP. The phosphorylated and unphosphorylated substrates were separated and detected by MSA device. The Km of CDK9-CCNK for its substrate is 88 μM.

Human

Sf9 insect cells

N-GST;N-Flag

P50750-1 (M1-F372)&O75909-1 (M1-S300)

1025&8812

≥ 90%, as determined by reducing SDS-PAGE.

Solution.

Supplied as a 0.2 μm filtered solution of 20 mM HEPES, pH 7.5, 200 mM NaCl, 5% glycerol, 1 mM DTT.

<1 EU/μg, determined by LAL method.

Please use rapid thawing with running water to thaw the protein.

Stored at -80°C for 1 year from date of receipt. 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.

• [1]. /biology-dictionary/p30-ohk-cell.html