Research Highlights

Short, accessible synopses of recent important articles concerning signalling pathways.

December 2007

• Tumour profiling: Networking, protein style

  

  Identifying cancer patients who are most at risk of developing metastases would undoubtedly save lives and also avoid overtreatment of some patients. Trey Ideker and colleagues asked whether including protein-network data alongside gene-expression data would improve the prediction of metastasis formation in patients with breast cancer.

  Original research paper Nature Reviews Cancer 7 892 - 893 doi:10.1038/nrc2277

• Tumour suppressors: WIP'ping up a storm

  

  Just when you thought it was safe to assume, in some small way, that you understood the regulation of the tumour suppressor p53 by the ubiquitin ligase MDM2, two papers published in Cancer Cell show just how wrong you can be.

  Original research paper Nature Reviews Cancer 7 896 doi:10.1038/nrc2276

• DNA-damage response: Chewing at the ends

  

  DNA double-strand breaks (DSBs) that occur in the S and G2 phases of the cell cycle are mainly repaired by homologous recombination (HR). HR is initiated by resection of the DNA strands surrounding a DSB, resulting in single-stranded DNA (ssDNA) that is bound by replication protein A (RPA). Consequently, strand invasion (an early step of HR) and recruitment of ataxia-telangiectasia and RAD3-related kinase (ATR; a kinase that mediates cell cycle checkpoint activation) establish the DNA-damage response. Stephen Jackson and colleagues now elaborate on the mechanism and control of DSB resection, a crucial step in the activation of specific DNA-damage-response pathways.

  Original research paper Nature Reviews Molecular Cell Biology 8 942 - 943 doi:10.1038/nrm2301

• Cell cycle: Passengers travel together

  

  The chromosomal passenger complex (CPC) regulates several mitotic events, including chromosome segregation and cytokinesis. The CPC consists of Aurora-B kinase and three regulatory subunits: INCENP, survivin and borealin. The targeting of Aurora-B by these subunits to the right substrate at the right place and time (to centromeres in metaphase and, later, to the central spindle and midbody) is crucial for the functioning of the CPC. Structural studies of the regulatory subunit complex shed new light on how interactions between these subunits relocalize the CPC during mitosis.

  Original research paper Nature Reviews Molecular Cell Biology 8 944 doi:10.1038/nrm2294

• Apoptosis: Recognizing 'eat-me' signals

  

  The clearance of apoptotic cells is crucial to avoid the development of autoimmune disease, and phosphatidylserine (PtdSer) on the surface of apoptotic cells is recognized as an engulfment signal by phagocytes. To date the receptors that directly recognize PtdSer had remained elusive, but now, two papers published in Nature report the identification of two PtdSer receptors.

  Original research paper Nature Reviews Immunology 7 917 doi:10.1038/nri2222