Issues

IQGAP1 is a scaffold protein for both the RAS/MAP kinase and PI 3-kinase signalling pathways, as shown on the right. Its WW domain, modelled on the left, has anti-tumour activity when engineered as a cell-penetrating peptide. The study by Bardwell and colleagues (pp. 729–750) shows that the catalytic subunit of PI 3-kinase, a known driver oncogene, is a direct binding partner of the WW domain, which could help explain its anti-tumour properties. The image was provided by Lee Bardwell.