Related Experiment Video
Updated: May 11, 2026

Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
Structure of the C-terminal region of p21(WAF1/CIP1) complexed with human PCNA
J M Gulbis1, Z Kelman, J Hurwitz
1Laboratory of Molecular Biophysics, The Rockefeller University, New York, New York 10021, USA.
Abstract:
The crystal structure of the human DNA polymerase delta processivity factor PCNA (proliferating cell nuclear antigen) complexed with a 22 residue peptide derived from the C-terminus of the cell-cycle checkpoint protein p21(WAF1/CIP1) has been determined at 2.6 angstrom resolution. p21 binds to PCNA in a 1:1 stoichiometry with an extensive array of interactions that include the formation of a beta sheet with the interdomain connector loop of PCNA. An intact trimeric ring is maintained in the structure of the p21-PCNA complex, with a central hole available for DNA interaction. The ability of p21 to inhibit the action of PCNA is therefore likely to be due to its masking of elements on PCNA that are required for the binding of other components of the polymerase assembly.
More Related Videos
09:04Sequence-specific and Selective Recognition of Double-stranded RNAs over Single-stranded RNAs by Chemically Modified Peptide Nucleic Acids
Published on: September 21, 2017
12:26Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay
Published on: May 3, 2018
Related Concept Videos
Histone Variants at the Centromere
DNA Damage can Stall the Cell Cycle
Restarting Stalled Replication Forks
Positive Regulator Molecules
Inhibition of Cdk Activity
Anaphase Promoting Complex