MDC1/NFBD1: a key regulator of the DNA damage response in higher eukaryotes

DNA Repair (Amst). Aug-Sep 2004;3(8-9):953-7. doi: 10.1016/j.dnarep.2004.03.007.


The protein MDC1/NFBD1 contains a forkhead-associated (FHA) domain and two BRCA1 carboxyl-terminal (BRCT) domains. It interacts with several proteins involved in DNA damage repair and checkpoint signalling, and is phosphorylated in response to DNA damage and during mitosis. Upon treatment of cultured human cells with DNA damaging agents, MDC1/NFBD1 translocates to sites of DNA lesions, where it collaborates with other proteins and with phosphorylated histone H2AX to mediate the accumulation of checkpoint and repair factors into nuclear foci. Down-regulation of MDC1/NFBD1 expression levels by small interfering RNA (siRNA) renders cells hyper-sensitive to DNA damaging agents and leads to defects in cell cycle checkpoint activation and apoptosis. Thus, MDC1/NFBD1 appears to be a key regulator of the DNA damage response in mammalian cells.

Publication types

  • Review

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Amino Acid Sequence
  • Animals
  • Cell Cycle Proteins
  • DNA Damage*
  • DNA Repair
  • DNA, Complementary / metabolism
  • DNA-Binding Proteins / physiology*
  • Histones / chemistry
  • Humans
  • Molecular Sequence Data
  • Nuclear Proteins / physiology*
  • Phosphorylation
  • Protein Structure, Tertiary
  • Protein Transport
  • RNA, Small Interfering / metabolism
  • Saccharomyces cerevisiae / metabolism
  • Sequence Homology, Amino Acid
  • Trans-Activators / physiology*


  • Adaptor Proteins, Signal Transducing
  • Cell Cycle Proteins
  • DNA, Complementary
  • DNA-Binding Proteins
  • H2AX protein, human
  • Histones
  • MDC1 protein, human
  • Nuclear Proteins
  • RNA, Small Interfering
  • Trans-Activators