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61.
62.
A physical map of the mouse genome 总被引:1,自引:0,他引:1
Gregory SG Sekhon M Schein J Zhao S Osoegawa K Scott CE Evans RS Burridge PW Cox TV Fox CA Hutton RD Mullenger IR Phillips KJ Smith J Stalker J Threadgold GJ Birney E Wylie K Chinwalla A Wallis J Hillier L Carter J Gaige T Jaeger S Kremitzki C Layman D Maas J McGrane R Mead K Walker R Jones S Smith M Asano J Bosdet I Chan S Chittaranjan S Chiu R Fjell C Fuhrmann D Girn N Gray C Guin R Hsiao L Krzywinski M Kutsche R Lee SS Mathewson C McLeavy C Messervier S Ness S Pandoh P Prabhu AL Saeedi P 《Nature》2002,418(6899):743-750
A physical map of a genome is an essential guide for navigation, allowing the location of any gene or other landmark in the chromosomal DNA. We have constructed a physical map of the mouse genome that contains 296 contigs of overlapping bacterial clones and 16,992 unique markers. The mouse contigs were aligned to the human genome sequence on the basis of 51,486 homology matches, thus enabling use of the conserved synteny (correspondence between chromosome blocks) of the two genomes to accelerate construction of the mouse map. The map provides a framework for assembly of whole-genome shotgun sequence data, and a tile path of clones for generation of the reference sequence. Definition of the human-mouse alignment at this level of resolution enables identification of a mouse clone that corresponds to almost any position in the human genome. The human sequence may be used to facilitate construction of other mammalian genome maps using the same strategy. 相似文献
63.
Isolation of an antifreeze peptide from the Antarctic sponge <Emphasis Type="Italic">Homaxinella balfourensis</Emphasis> 总被引:1,自引:0,他引:1
Wilkins SP Blum AJ Burkepile DE Rutland TJ Wierzbicki A Kelly M Hamann MT 《Cellular and molecular life sciences : CMLS》2002,59(12):2210-2215
Polar plants and animals survive in subzero waters (-2 degrees C) and many of these marine organisms produce antifreeze proteins (AFPs) to better adapt themselves to these conditions. AFPs prevent the growth of ice crystals which disrupt cellular membranes and destroy cells by inhibiting crystallization of water within the organism. The hydrophilic extract of an Antarctic sponge Homaxinella balfourensis exhibited a non-colligative freezing point depression effect on the crystal morphology of water. The extract was purified by repeated reverse phase high-pressure liquid chromatography, then assayed and shown to contain several AFPs. The major peptide was isolated, analyzed using matrix-assisted laser desorption ionization mass spectrometry and the partial structure of the peptide identified through amino acid sequencing. AFPs have potential applications in agriculture, medicine and the food industry. 相似文献
64.
Seeds from 12 grass species were studied relative to mode of wetting and time of exposure to water to document interspecific differences in imbibition characteristics. Imbibition causes seeds to become wet, and wet seeds are more detectable to consumers than dry seeds. Thus, germination potential and ability to remain undetected by consumers may represent an important trade-off. Seeds wetted for 0-192 h in vials imbibed water at rates equivalent to seeds wetted by contact with wet paper towels pressing against their seed coat, except for seeds of Avena sativa , which weighed more after wetting in 2-mL vials with free water (0.471 g vs. 0.432 g). Seeds from different species imbibed water at different rates. These data show that interspecific variation in imbibition for seeds is high and support an expectation that imbibition potential can interact with detectability to consumers in an evolutionary trade-off. 相似文献
65.
Kelly W. Allred 《西北部美国博物学家》2011,52(1)
Collection data, bibliographic citations, and curatorial information on 52 names of New Mexico grass types are compiled. A bibliography of taxonomic research pertinent to the study of New Mexico grasses is cross-referenced with genera known to occur in the state. 相似文献
66.
David M. Stoms Frank W. Davis Kenneth L. Driese Kelly M. Cassidy Michael P. Murray 《西北部美国博物学家》2011,58(3)
A conservation gap analysis was conducted for the Intermountain Semi-Desert ecoregion to assess the representation of land-cover types within areas managed primarily for biodiversity objectives. Mapped distributions of plant communities were summarized by land-management status categories. The total amount of land permanently protected in the ecoregion is < 4%, and most types that are characteristic of the region have < 10%. Of 48 land-cover types, 20 were found to be particularly vulnerable to potential loss or degradation because of low level of representation in biodiversity management areas and the impact of expected land-use activities. Gap analysis data and findings will be useful in providing a regional perspective in project impact assessment and future conservation planning within this ecoregion. 相似文献
67.
68.
9p21 DNA variants associated with coronary artery disease impair interferon-γ signalling response 总被引:1,自引:0,他引:1
Harismendy O Notani D Song X Rahim NG Tanasa B Heintzman N Ren B Fu XD Topol EJ Rosenfeld MG Frazer KA 《Nature》2011,470(7333):264-268
69.
70.
Lorenzen ED Nogués-Bravo D Orlando L Weinstock J Binladen J Marske KA Ugan A Borregaard MK Gilbert MT Nielsen R Ho SY Goebel T Graf KE Byers D Stenderup JT Rasmussen M Campos PF Leonard JA Koepfli KP Froese D Zazula G Stafford TW Aaris-Sørensen K Batra P Haywood AM Singarayer JS Valdes PJ Boeskorov G Burns JA Davydov SP Haile J Jenkins DL Kosintsev P Kuznetsova T Lai X Martin LD McDonald HG Mol D Meldgaard M Munch K Stephan E Sablin M Sommer RS Sipko T Scott E Suchard MA Tikhonov A Willerslev R 《Nature》2011,479(7373):359-364
Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary period remain contentious. Here we use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, emphasizing the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change. 相似文献