Research Highlights

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

September 2008

• Tumour suppression: Sharing the limelight

  

  The cell surface membrane protein CD44 is now an 'A-list' molecule owing to its expression on stem (and potential cancer stem) cells. However, new data from Samuel Godar, Robert Weinberg and colleagues suggest that CD44 might have to share its new-found fame with an old pro, p53.

  Original research paper Nature Reviews Cancer 8 660 - 661 doi:10.1038/nrc2470

• Migration: RAB goes back to RAC

  

  Growth factor signalling is mediated by membrane receptor tyrosine kinases (RTKs) and induces cell motility through the activation of RAC1 — a small Rho GTPase known to be a key coordinator in actin remodelling. Reporting in Cell, Palamidessi et al. show that RAB5-dependent endocytosis is a requirement for spatially restricted RAC1 activation that occurs downstream of RTKs. The delivery of active RAC1 to specific plasma membrane regions ensures the formation of the actin protrusions that are important for directed migration.

  Original research paper Nature Reviews Cancer 8 662 - 663 doi:10.1038/nrc2476

• Immune regulation: Tripping a tissue-specific switch

  

  Different organs of the body have tissue-specific mechanisms in place to regulate the threshold of immune responses and resolve inflammation. A recent study in Nature Immunology has now shown that a homeostatic loop involving CD200 and its receptor (CD200R) is an important regulator of steady-state immune homeostasis and inflammation in the airways.

  Original research paper Nature Reviews Immunology 8 659 doi:10.1038/nri2398

• Tumorigenesis: Two-faced

  

  Menin is an intriguing protein. It is mutated in patients with multiple endocrine neoplasia type 1, and therefore functions as a tumour suppressor in these tissues. However, it is also essential for leukaemogenesis induced by oncogenic forms of the histone methyltransferase mixed lineage leukaemia (MLL). A paper published recently in Cancer Cell indicates how menin might achieve this volte-face.

  Original research paper Nature Reviews Cancer 8 657 doi:10.1038/nrc2469

• We the curators

  

  Two groups describe wiki platforms for community-based curation of gene annotations or biological pathways.

  Original research paper Nature Methods 5 754 - 755 doi:10.1038/nmeth0908-754a