Impacts of experimental warming and fire on phenology of subalpine open-heath species

The present study examined experimentally the phenological responses of a range of plant species to rises in temperature. We used the climate-change field protocol of the International Tundra Experiment (ITEX), which measures plant responses to warming of 1 to 2°C inside small open-topped chambers. The field study was established on the Bogong High Plains, Australia, in subalpine open heathlands; the most common treeless plant community on the Bogong High Plains. The study included areas burnt by fire in 2003, and therefore considers the interactive effects of warming and fire, which have rarely been studied in high mountain environments. From November 2003 to March 2006, various phenological phases were monitored inside and outside chambers during the snow-free periods. Warming resulted in earlier occurrence of key phenological events in 7 of the 14 species studied. Burning altered phenology in 9 of 10 species studied, with both earlier and later phenological changes depending on the species. There were no common phenological responses to warming or burning among species of the same family, growth form or flowering type (i.e. early or late-flowering species), when all phenological events were examined. The proportion of plants that formed flower buds was influenced by fire in half of the species studied. The findings support previous findings of ITEX and other warming experiments; that is, species respond individualistically to experimental warming. The inter-year variation in phenological response, the idiosyncratic nature of the responses to experimental warming among species, and an inherent resilience to fire, may result in community resilience to short-term climate change. In the first 3 years of experimental warming, phenological responses do not appear to be driving community-level change. Our findings emphasise the value of examining multiple species in climate-change studies

Discovery of 1‑(3,3-Dimethylbutyl)-3-(2-fluoro-4-methyl-5-(7-methyl-2-(methylamino)­pyrido[2,3‑<i>d</i>]pyrimidin-6-yl)phenyl)urea (LY3009120) as a Pan-RAF Inhibitor with Minimal Paradoxical Activation and Activity against <i>BRAF</i> or <i>RAS</i> Mutant Tumor Cells

The RAS-RAF-MEK-MAPK cascade is an essential signaling pathway, with activation typically mediated through cell surface receptors. The kinase inhibitors vemurafenib and dabrafenib, which target oncogenic BRAF V600E, have shown significant clinical efficacy in melanoma patients harboring this mutation. Because of paradoxical pathway activation, both agents were demonstrated to promote growth and metastasis of tumor cells with <i>RAS</i> mutations in preclinical models and are contraindicated for treatment of cancer patients with <i>BRAF</i> WT background, including patients with <i>KRAS</i> or <i>NRAS</i> mutations. In order to eliminate the issues associated with paradoxical MAPK pathway activation and to provide therapeutic benefit to patients with <i>RAS</i> mutant cancers, we sought to identify a compound not only active against BRAF V600E but also wild type BRAF and CRAF. On the basis of its superior in vitro and in vivo profile, compound <b>13</b> was selected for further development and is currently being evaluated in phase I clinical studies