Browsing by Subject "Flight, Animal"

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    Comparative genomics reveals insights into avian genome evolution and adaptation.
    (Science, 2014-12-12) Zhang, Guojie; Li, Cai; Li, Qiye; Li, Bo; Larkin, Denis M; Lee, Chul; Storz, Jay F; Antunes, Agostinho; Greenwold, Matthew J; Meredith, Robert W; Ödeen, Anders; Cui, Jie; Zhou, Qi; Xu, Luohao; Pan, Hailin; Wang, Zongji; Jin, Lijun; Zhang, Pei; Hu, Haofu; Yang, Wei; Hu, Jiang; Xiao, Jin; Yang, Zhikai; Liu, Yang; Xie, Qiaolin; Yu, Hao; Lian, Jinmin; Wen, Ping; Zhang, Fang; Li, Hui; Zeng, Yongli; Xiong, Zijun; Liu, Shiping; Zhou, Long; Huang, Zhiyong; An, Na; Wang, Jie; Zheng, Qiumei; Xiong, Yingqi; Wang, Guangbiao; Wang, Bo; Wang, Jingjing; Fan, Yu; da Fonseca, Rute R; Alfaro-Núñez, Alonzo; Schubert, Mikkel; Orlando, Ludovic; Mourier, Tobias; Howard, Jason T; Ganapathy, Ganeshkumar; Pfenning, Andreas; Whitney, Osceola; Rivas, Miriam V; Hara, Erina; Smith, Julia; Farré, Marta; Narayan, Jitendra; Slavov, Gancho; Romanov, Michael N; Borges, Rui; Borges, Rui; Machado, João Paulo; Khan, Imran; Springer, Mark S; Gatesy, John; Hoffmann, Federico G; Opazo, Juan C; Håstad, Olle; Sawyer, Roger H; Kim, Heebal; Kim, Kyu-Won; Kim, Hyeon Jeong; Cho, Seoae; Li, Ning; Huang, Yinhua; Bruford, Michael W; Zhan, Xiangjiang; Dixon, Andrew; Bertelsen, Mads F; Derryberry, Elizabeth; Warren, Wesley; Wilson, Richard K; Li, Shengbin; Ray, David A; Green, Richard E; O'Brien, Stephen J; Griffin, Darren; Johnson, Warren E; Haussler, David; Ryder, Oliver A; Willerslev, Eske; Graves, Gary R; Alström, Per; Fjeldså, Jon; Mindell, David P; Edwards, Scott V; Braun, Edward L; Rahbek, Carsten; Burt, David W; Houde, Peter; Zhang, Yong; Yang, Huanming; Wang, Jian; Avian Genome Consortium; Jarvis, Erich D; Gilbert, M Thomas P; Wang, Jun
    Birds are the most species-rich class of tetrapod vertebrates and have wide relevance across many research fields. We explored bird macroevolution using full genomes from 48 avian species representing all major extant clades. The avian genome is principally characterized by its constrained size, which predominantly arose because of lineage-specific erosion of repetitive elements, large segmental deletions, and gene loss. Avian genomes furthermore show a remarkably high degree of evolutionary stasis at the levels of nucleotide sequence, gene synteny, and chromosomal structure. Despite this pattern of conservation, we detected many non-neutral evolutionary changes in protein-coding genes and noncoding regions. These analyses reveal that pan-avian genomic diversity covaries with adaptations to different lifestyles and convergent evolution of traits.
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    Electron tomography of cryofixed, isometrically contracting insect flight muscle reveals novel actin-myosin interactions.
    (PLoS One, 2010-09-09) Wu, Shenping; Liu, Jun; Reedy, Mary C; Tregear, Richard T; Winkler, Hanspeter; Franzini-Armstrong, Clara; Sasaki, Hiroyuki; Lucaveche, Carmen; Goldman, Yale E; Reedy, Michael K; Taylor, Kenneth A
    BACKGROUND: Isometric muscle contraction, where force is generated without muscle shortening, is a molecular traffic jam in which the number of actin-attached motors is maximized and all states of motor action are trapped with consequently high heterogeneity. This heterogeneity is a major limitation to deciphering myosin conformational changes in situ. METHODOLOGY: We used multivariate data analysis to group repeat segments in electron tomograms of isometrically contracting insect flight muscle, mechanically monitored, rapidly frozen, freeze substituted, and thin sectioned. Improved resolution reveals the helical arrangement of F-actin subunits in the thin filament enabling an atomic model to be built into the thin filament density independent of the myosin. Actin-myosin attachments can now be assigned as weak or strong by their motor domain orientation relative to actin. Myosin attachments were quantified everywhere along the thin filament including troponin. Strong binding myosin attachments are found on only four F-actin subunits, the "target zone", situated exactly midway between successive troponin complexes. They show an axial lever arm range of 77°/12.9 nm. The lever arm azimuthal range of strong binding attachments has a highly skewed, 127° range compared with X-ray crystallographic structures. Two types of weak actin attachments are described. One type, found exclusively in the target zone, appears to represent pre-working-stroke intermediates. The other, which contacts tropomyosin rather than actin, is positioned M-ward of the target zone, i.e. the position toward which thin filaments slide during shortening. CONCLUSION: We present a model for the weak to strong transition in the myosin ATPase cycle that incorporates azimuthal movements of the motor domain on actin. Stress/strain in the S2 domain may explain azimuthal lever arm changes in the strong binding attachments. The results support previous conclusions that the weak attachments preceding force generation are very different from strong binding attachments.