UNIT 12.5 UV Crosslinking of Proteins to Nucleic Acids

  1. Lewis A. Chodosh

Published Online: 1 MAY 2001

DOI: 10.1002/0471142727.mb1205s36

Current Protocols in Molecular Biology

Current Protocols in Molecular Biology

How to Cite

Chodosh, L. A. 2001. UV Crosslinking of Proteins to Nucleic Acids. Current Protocols in Molecular Biology. 36:12.5:12.5.1–12.5.8.

Author Information

  1. Massachusetts Institute of Technology and Harvard Medical School, Cambridge and Boston, Massachusetts

Publication History

  1. Published Online: 1 MAY 2001
  2. Published Print: OCT 1996


Irradiation of protein-nucleic acid complexes with ultraviolet light causes covalent bonds to form between the nucleic acid and proteins that are in close contact with the nucleic acid. Thus, UV crosslinking may be used to selectively label DNA-binding proteins based on their specific interaction with a DNA recognition site. As a consequence of label transfer, the molecular weight of a DNA-binding protein in a crude mixture can be rapidly and reliably determined. This unit provides 3 protocols for executing DNA-protein crosslinking; one uses the halogenated thymidine analog bromodeoxyuridine (BrdU) to produce a DNA probe that is especially sensitive to UV-induced crosslinking. An alternate protocol describes crosslinking using a non-BrdU substituted probe, and another alternate protocol provides a method for in situ crosslinking.