Blogging a crystal structure a day in 2014


Contributed by

Róisín McMahon

A little helper – Elf3

What is it?

E74-like factor-3 (Elf3) is a transcription factor. This means that it is a protein involved in the expression of genes. Elf3 works with other proteins to regulate genes involved in inflammation and cancer; it is has been found to be abnormally expressed in some lung and breast cancers.

In order to ensure proper gene expression, transcription factor activity is highly regulated. Accordingly Elf3 is held in an "off" state and must be specifically turned on before it can bind to DNA to start gene expression. The interaction of Elf3 with DNA is also highly specific, again to avoid abnormal gene expression that may lead to disease.

In order to learn how Elf3 recognises, binds and activates gene expression, researchers solved the crystal structure of the Elf3 bound to DNA from one of its target genes.

What does it look like?


This structure is of a specific part of mouse Elf3, the so-called E-twenty-six (Ets) domain, bound to DNA from mouse Type II TGF-b receptor promoter. Promoter DNA sequences provide a "start to read me from here" instruction to transcription factors so this structure provides lots of information about how the two molecules talk to each other.

Elf3 (green) is shown bound to DNA (red double helix).

Where did the structure come from?

This structure is PDB ID 3JTH1.


  1. Agarkar et al., Journal of Molecular Biology, 2010. 397, 278-289