4EC8: Structure Of Full Length Cdk9 In Complex With Cyclint And Drb

CDK9, the kinase of positive transcription elongation factor b (P-TEFb), stimulates transcription elongation by phosphorylating RNA polymerase II and transcription elongation factors. Using kinetic analysis of a human P-TEFb complex consisting of CDK9 and cyclin T, we show that the CDK9 C-terminal tail sequence is important for the catalytic mechanism and imposes an ordered binding of substrates and release of products. Crystallographic analysis of a CDK9/cyclin T complex in which the C-terminal tail partially blocks the ATP binding site reveals a possible reaction intermediate. Biochemical characterization of CDK9 mutants supports a model in which the CDK9 tail cycles through different conformational states. We propose that this mechanism is critical for the pattern of CTD Ser2 phosphorylation on actively transcribed genes.
PDB ID: 4EC8Download
MMDB ID: 102851
PDB Deposition Date: 2012/3/26
Updated in MMDB: 2014/10
Experimental Method:
x-ray diffraction
Resolution: 3.6  Å
Source Organism:
Similar Structures:
Biological Unit for 4EC8: dimeric; determined by author and by software (PISA)
Molecular Components in 4EC8
Label Count Molecule
Proteins (2 molecules)
Cyclin-dependent Kinase 9(Gene symbol: CDK9)
Molecule annotation
Cyclin-t1(Gene symbol: CCNT1)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB