ALBERT

Description: Snowfall was measured at 11 sites in the McMurdo Dry Valleys to determine its magnitude, its temporal changes, and spatial patterns. Annual values ranged from 3 to 50 mm water equivalent with the highest values nearest the coast and decreasing inland. A particularly strong spatial gradient exists in Taylor Valley, probably resulting from local uplift conditions at the coastal margin and valley topography that limits migration inland. More snow occurs in winter near the coast, whereas inland no seasonal pattern is discernable. This may be due, again, to local uplift conditions, which are common in winter. We find no influence of the distance to the sea ice edge. Katabatic winds play an important role in transporting snow to the valley bottoms and essentially double the precipitation. That much of the snow accumulation sublimates prior to making a hydrologic contribution underscores the notion that the McMurdo Dry Valleys are indeed an extreme polar desert.

Description: Legumes (Fabaceae or Leguminosae) are unique among cultivated plants for their ability to carry out endosymbiotic nitrogen fixation with rhizobial bacteria, a process that takes place in a specialized structure known as the nodule. Legumes belong to one of the two main groups of eurosids, the Fabidae, which includes most species capable of endosymbiotic nitrogen fixation. Legumes comprise several evolutionary lineages derived from a common ancestor 60 million years ago (Myr ago). Papilionoids are the largest clade, dating nearly to the origin of legumes and containing most cultivated species. Medicago truncatula is a long-established model for the study of legume biology. Here we describe the draft sequence of the M. truncatula euchromatin based on a recently completed BAC assembly supplemented with Illumina shotgun sequence, together capturing approximately 94% of all M. truncatula genes. A whole-genome duplication (WGD) approximately 58 Myr ago had a major role in shaping the M. truncatula genome and thereby contributed to the evolution of endosymbiotic nitrogen fixation. Subsequent to the WGD, the M. truncatula genome experienced higher levels of rearrangement than two other sequenced legumes, Glycine max and Lotus japonicus. M. truncatula is a close relative of alfalfa (Medicago sativa), a widely cultivated crop with limited genomics tools and complex autotetraploid genetics. As such, the M. truncatula genome sequence provides significant opportunities to expand alfalfa's genomic toolbox.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3272368/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3272368/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Young, Nevin D -- Debelle, Frederic -- Oldroyd, Giles E D -- Geurts, Rene -- Cannon, Steven B -- Udvardi, Michael K -- Benedito, Vagner A -- Mayer, Klaus F X -- Gouzy, Jerome -- Schoof, Heiko -- Van de Peer, Yves -- Proost, Sebastian -- Cook, Douglas R -- Meyers, Blake C -- Spannagl, Manuel -- Cheung, Foo -- De Mita, Stephane -- Krishnakumar, Vivek -- Gundlach, Heidrun -- Zhou, Shiguo -- Mudge, Joann -- Bharti, Arvind K -- Murray, Jeremy D -- Naoumkina, Marina A -- Rosen, Benjamin -- Silverstein, Kevin A T -- Tang, Haibao -- Rombauts, Stephane -- Zhao, Patrick X -- Zhou, Peng -- Barbe, Valerie -- Bardou, Philippe -- Bechner, Michael -- Bellec, Arnaud -- Berger, Anne -- Berges, Helene -- Bidwell, Shelby -- Bisseling, Ton -- Choisne, Nathalie -- Couloux, Arnaud -- Denny, Roxanne -- Deshpande, Shweta -- Dai, Xinbin -- Doyle, Jeff J -- Dudez, Anne-Marie -- Farmer, Andrew D -- Fouteau, Stephanie -- Franken, Carolien -- Gibelin, Chrystel -- Gish, John -- Goldstein, Steven -- Gonzalez, Alvaro J -- Green, Pamela J -- Hallab, Asis -- Hartog, Marijke -- Hua, Axin -- Humphray, Sean J -- Jeong, Dong-Hoon -- Jing, Yi -- Jocker, Anika -- Kenton, Steve M -- Kim, Dong-Jin -- Klee, Kathrin -- Lai, Hongshing -- Lang, Chunting -- Lin, Shaoping -- Macmil, Simone L -- Magdelenat, Ghislaine -- Matthews, Lucy -- McCorrison, Jamison -- Monaghan, Erin L -- Mun, Jeong-Hwan -- Najar, Fares Z -- Nicholson, Christine -- Noirot, Celine -- O'Bleness, Majesta -- Paule, Charles R -- Poulain, Julie -- Prion, Florent -- Qin, Baifang -- Qu, Chunmei -- Retzel, Ernest F -- Riddle, Claire -- Sallet, Erika -- Samain, Sylvie -- Samson, Nicolas -- Sanders, Iryna -- Saurat, Olivier -- Scarpelli, Claude -- Schiex, Thomas -- Segurens, Beatrice -- Severin, Andrew J -- Sherrier, D Janine -- Shi, Ruihua -- Sims, Sarah -- Singer, Susan R -- Sinharoy, Senjuti -- Sterck, Lieven -- Viollet, Agnes -- Wang, Bing-Bing -- Wang, Keqin -- Wang, Mingyi -- Wang, Xiaohong -- Warfsmann, Jens -- Weissenbach, Jean -- White, Doug D -- White, Jim D -- Wiley, Graham B -- Wincker, Patrick -- Xing, Yanbo -- Yang, Limei -- Yao, Ziyun -- Ying, Fu -- Zhai, Jixian -- Zhou, Liping -- Zuber, Antoine -- Denarie, Jean -- Dixon, Richard A -- May, Gregory D -- Schwartz, David C -- Rogers, Jane -- Quetier, Francis -- Town, Christopher D -- Roe, Bruce A -- BB/G023832/1/Biotechnology and Biological Sciences Research Council/United Kingdom -- BBS/B/11524/Biotechnology and Biological Sciences Research Council/United Kingdom -- England -- Nature. 2011 Nov 16;480(7378):520-4. doi: 10.1038/nature10625.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Plant Pathology, University of Minnesota, St Paul, Minnesota 55108, USA. neviny@umn.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/22089132" target="_blank"〉PubMed〈/a〉