WOW! A busy week in the bioscience world…
Pull Down Your ‘SOCS’ and Grow Some Nerves: A long standing question is how to get mature neurons, which stop growing at around the age of two, to start growing again after sustaining nerve damage. The answer may lie in a protein called SOCS3 (suppressor of cytokine signaling 3). SOCS3 controls neuronal growth in adults but when it is absent (in a knockout mouse model), axons can regenerate after nerve injury. This process may be enhanced by supplying a cocktail of neurotrophic growth factors that the researchers also identified in their study. This is a very important discovery that will push regenerative medicine to new therapeutic strategies. Dr. Patrice Smith started the research as a postdoctoral fellow at Harvard University and now runs her own lab at Carleton University. The study is published in the latest edition of Neuron. There is also an inspirational story about Dr. Smith in the Globe and Mail.
Protecting your Brain after a Stroke: Following a stroke, neurons are at risk of permanent damage caused by overactivation of NMDARs (N-methyl-D-aspartate glutamate receptors). A key molecular step leading to this excitotoxic neuronal death was discovered in this recent study. The trauma causes degradation of Insig-1 (insulin-induced gene-1), which triggers the activation of the transcription factor SREBP-1 (sterol regulatory element binding protein-1). However, when they blocked the activation of SREBP-1 they were successful in reducing the neuronal damage. This is a promising target for generating therapeutic drugs aimed at minimizing the detrimental effects of strokes and brain trauma. The research team was guided by Dr. Yu Tian Wang at the University of British Columbia and the study is reported in the latest Nature Medicine.
Breakthrough in Children’s Brain Cancer Research: A rare pediatric brain tumour called Central Nervous System-Primitive Neuroectodermal Tumours (CNS-PNET) offers a very poor prognosis for young patients. In this gene expression study, a cluster of microRNAs called C19MC was found to be amplified in the diseased tissue in about 25% of the patients. This cluster acts as an oncogene that enhances cell growth and affects differentiation of neural stem cells. The new discovery will advance opportunities to study this rare pediatric cancer and possibly use C19MC as a diagnostic marker and/or therapeutic target. The international study was led by Dr. Annie Huang at SickKids Hospital and is reported in the current issue of Cancer Cell.
Genomics Study on Pathogenic Factors: In a large scale study of bacterial genomes, it was proven broadly across microbial species that many of the bacterial virulence factors are contained within genomic islands or clusters of genes. The virulence factors are proteins that have more “offensive” functions such as toxins that help the bacteria invade the host. Another significant outcome of this research is the discovery of potentially new pathogen-associated genes that are present pre-dominantly in pathogenic bacteria but less frequently in the non-pathogenic bacteria. These factors require a closer look as they may represent novel targets for anti-microbial drug development, a critical area of research to combat the increasing prevalence of drug resistant bacteria. Dr. Fiona Brinkman’s team at Simon Fraser University conducted the research and is detailed in PLoS One.
Dabigatran vs. Warfarin (round 2): Following up on a study that I mentioned here earlier this year, new research further supports the use of Dabigatran over Warfarin. Patients with a common clotting disorder called venous thromboembolism (VTE) can benefit from Dabigatran as an equally effective and safe blood thinning treatment but without the complications associated with using Warfarin, which requires frequent visits to the clinic for blood monitoring and dosage adjustments. The study was conducted by Dr. Sam Schulman at McMaster University and appears in this week’s The New England Journal of Medicine.
Research on Congenital Myopathy in Mice: University of Toronto scientists have generated a mouse model to study a specific type of skeletal muscle disorder. The mice express a mutant form of the RyR1 protein (type 1 ryanodine receptor/Ca2+ release channel), which causes a severe form of central core disease (CCD). Symptoms in mice that mimic the human condition include progressive congenital myopathy, respiratory stress, skeletal muscle weakness and impaired mobility. Their study offers insight and future potential to unravel the mechanism behind the disorder. Dr. David MacLennan’s research is published in The Proceedings of the National Academy of Sciences.
Here is a list of many more important research reports this week from across the country:
Cofactor-activated phosphorylation is required for inhibition of cortical neuron differentiation by Groucho/TLE1. (Dr. Stefano Stifani, McGill University)
Dlx5 Is a cell autonomous regulator of chondrocyte hypertrophy in mice and functionally substitutes for Dlx6 during endochondral ossification. (Dr. Andrew Bendall, University of Guelph)
Pluripotent transcription factors possess distinct roles in normal versus transformed human stem cells. (Dr. Mickie Bhatia, McMaster University)
Nfil3/E4bp4 is required for the development and maturation of NK cells in vivo. (Dr. Tak Mak, The Campbell Family Institute for Breast Cancer Research and University of Toronto).
A novel enediynyl peptide inhibitor of furin that blocks processing of proPDGF-A, B and proVEGF-C. (Dr. Amik Basak, University of Ottawa)
The specificity of the FOXL2 c.402C>G Somatic mutation: a survey of solid tumors. (Dr. David Huntsman, University of British Columbia)
Nuclear function of Smad7 promotes myogenesis. (Dr. John McDermott, York University)
Asf1-like structure of the conserved Yaf9 YEATS domain and role in H2A.Z deposition and acetylation. (Dr. Michael Kobor, University of British Columbia)