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911.
912.
AA Aksyuk VD Bowman B Kaufmann C Fields T Klose HA Holdaway VA Fischetti MG Rossmann 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(35):14001-14006
The Podoviridae phage C1 was one of the earliest isolated bacteriophages and the first virus documented to be active against streptococci. The icosahedral and asymmetric reconstructions of the virus were calculated using cryo-electron microscopy. The capsid protein has an HK97 fold arranged into a T = 4 icosahedral lattice. The C1 tail is terminated with a φ29-like knob, surrounded by a skirt of twelve long appendages with novel morphology. Several C1 structural proteins have been identified, including a candidate for an appendage. The crystal structure of the knob has an N-terminal domain with a fold observed previously in tube forming proteins of Siphoviridae and Myoviridae phages. The structure of C1 suggests the mechanisms by which the virus digests the cell wall and ejects its genome. Although there is little sequence similarity to other phages, conservation of the structural proteins demonstrates a common origin of the head and tail, but more recent evolution of the appendages. 相似文献
913.
Jarvis E Bruce HS Patel NH 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(Z1):10634-10639
The diverse array of body plans possessed by arthropods is created by generating variations upon a design of repeated segments formed during development, using a relatively small "toolbox" of conserved patterning genes. These attributes make the arthropod body plan a valuable model for elucidating how changes in development create diversity of form. As increasingly specialized segments and appendages evolved in arthropods, the nervous systems of these animals also evolved to control the function of these structures. Although there is a remarkable degree of conservation in neural development both between individual segments in any given species and between the nervous systems of different arthropod groups, the differences that do exist are informative for inferring general principles about the holistic evolution of body plans. This review describes developmental processes controlling neural segmentation and regionalization, highlighting segmentation mechanisms that create both ectodermal and neural segments, as well as recent studies of the role of Hox genes in generating regional specification within the central nervous system. We argue that this system generates a modular design that allows the nervous system to evolve in concert with the body segments and their associated appendages. This information will be useful in future studies of macroevolutionary changes in arthropod body plans, especially in understanding how these transformations can be made in a way that retains the function of appendages during evolutionary transitions in morphology. 相似文献
914.
915.
Renhai Cao Hong Ji Ninghan Feng Yin Zhang Xiaojuan Yang Patrik Andersson Yuping Sun Katerina Tritsaris Anker Jon Hansen Steen Dissing Yihai Cao 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(39):15894-15899
Interplay between various lymphangiogenic factors in promoting lymphangiogenesis and lymphatic metastasis remains poorly understood. Here we show that FGF-2 and VEGF-C, two lymphangiogenic factors, collaboratively promote angiogenesis and lymphangiogenesis in the tumor microenvironment, leading to widespread pulmonary and lymph-node metastases. Coimplantation of dual factors in the mouse cornea resulted in additive angiogenesis and lymphangiogenesis. At the molecular level, we showed that FGFR-1 expressed in lymphatic endothelial cells is a crucial receptor that mediates the FGF-2–induced lymphangiogenesis. Intriguingly, the VEGFR-3–mediated signaling was required for the lymphatic tip cell formation in both FGF-2– and VEGF-C–induced lymphangiogenesis. Consequently, a VEGFR-3–specific neutralizing antibody markedly inhibited FGF-2–induced lymphangiogenesis. Thus, the VEGFR-3–induced lymphatic endothelial cell tip cell formation is a prerequisite for FGF-2–stimulated lymphangiogenesis. In the tumor microenvironment, the reciprocal interplay between FGF-2 and VEGF-C collaboratively stimulated tumor growth, angiogenesis, intratumoral lymphangiogenesis, and metastasis. Thus, intervention and targeting of the FGF-2– and VEGF-C–induced angiogenic and lymphangiogenic synergism could be potentially important approaches for cancer therapy and prevention of metastasis. 相似文献
916.
ILR Genetics Consortium Emerging Risk Factors Collaboration Sarwar N Butterworth AS Freitag DF Gregson J Willeit P Gorman DN Gao P Saleheen D Rendon A Nelson CP Braund PS Hall AS Chasman DI Tybjærg-Hansen A Chambers JC Benjamin EJ Franks PW Clarke R Wilde AA Trip MD Steri M Witteman JC Qi L van der Schoot CE de Faire U Erdmann J Stringham HM Koenig W Rader DJ Melzer D Reich D Psaty BM Kleber ME Panagiotakos DB Willeit J Wennberg P Woodward M Adamovic S Rimm EB Meade TW Gillum RF Shaffer JA 《Lancet》2012,379(9822):1205-1213
917.
Cialone J Adams H Augustine EF Marshall FJ Kwon JM Newhouse N Vierhile A Levy E Dure LS Rose KR Ramirez-Montealegre D de Blieck EA Mink JW 《Journal of inherited metabolic disease》2012,35(3):549-555
Juvenile neuronal ceroid lipofuscinosis (JNCL; CLN3 disease; Batten disease) is an autosomal recessive neurodegenerative disease of childhood. Symptoms typically present at school age with vision loss followed by progressive cognitive decline, motor dysfunction, seizures, and behavior problems. Studies on sex differences in JNCL have yielded mixed results, but parent anecdotes suggest that females experience a more precipitous disease course. Therefore, we sought to determine if sex-based differences exist in JNCL. We used data from the Unified Batten Disease Rating Scale (UBDRS), the Batten Disease Support and Research Association (BDSRA) database, and the PedsQL quality of life (QoL) survey to evaluate sex-based differences in functional independence and time from symptom onset to death. On average, females had JNCL symptom onset one year later and death one year earlier than did males. Despite a later age at onset, females had lower functional capability, earlier loss of independent function, and lower physical QoL. Future research in sex differences in JNCL may help to further understand the biological mechanisms underpinning the disease course and may point to targeted therapies. 相似文献
918.
919.