Scientists at Johns Hopkins School of Medicine set out to systematically map protein-DNA interactions across the human genome using a combination of bioinformatics and a protein-microarray strategy. Their exploration of the protein-DNA interactome identified over 17,000 interactions between 460 DNA sequences predicted to regulate transcription and 4191 proteins of varied functional classes. As well as finding known transcription factors (TFs), the work uncovered a large number of previously uncharacterised TFs. Of the unconventional DNA-binding proteins, over 300 exhibited sequence-specific DNA-binding.

One example of the sequence-specific DNA binders identified was ERK2 (MAP kinase-1), a serine/threonine kinase involved in cellular signalling. The Johns Hopkins team found that ERK2 is a transcriptional repressor of interferon-γ inducible genes and that this function is independent of its catalytic kinase activity. Whilst ERK2 has been extensively studied because of its importance in regulation of cellular proliferation, this unexpected additional role of ERK2 adds another level of complexity. Knowledge of the transcriptional repressor function may shed new light on knock-out experiments with ERK2.

The study, published in the journal Cell, examined only a fraction of the human proteome, raising the possibility that there may be thousands of proteins that also function as transcription factors. Certainly something else to consider in drug discovery when your enzyme inhibitor doesn’t do the same as the knockout!

Related posts:

  1. Role for PEAK1 Kinase in Tumour Metastasis The cytoskeleton plays a key role in regulating many cellular functions; it maintains cell shape, protects the cell, enables cellular...
  2. Role for ROCK in Cavernous Malformation Cerebral cavernous malformations (CCM) are irregular clusters of dilated, leaky capillaries found in the central nervous system in around 0.5%...
  3. ‘Notching’ up a Victory for Drug Design Transcription factors – proteins that bind to specific DNA sequences and promote or block transcription – are essential for correct...
  4. LRRK2 Inhibitor Protective in Parkinson’s Disease Model The main symptoms of Parkinson’s disease are tremor, rigidity and involuntary movement, caused by loss of dopaminergic neurons in the...
  5. Just Another Kinase Structure? The Janus family of protein tyrosine kinases is comprised of four members: JAK-1, JAK-2, JAK-3 and Tyk-2. These kinases provide...

Related posts brought to you by Yet Another Related Posts Plugin.

This entry was posted on Wednesday, November 4th, 2009 at 8:36 am and is filed under News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

Leave a Reply