Regulation of CDK9 Activity by Phosphorylation and Dephosphorylation

Figure 2

Structure of CDK9/cyclin T1/Tat complex (model based on PDB 3MIA). Backbone representation of CDK9 residues present in original PDB structure is shown in green color, cyclin T1—in violet, and Tat—in red. Position of Thr-29, Ser-175, Thr-186, and C-terminal Ser/Thr cluster is indicated. Also shown are ATP-binding site and Zn ions that facilitate Tat-cyclin T1 interaction.