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311.
The optic tectum controls visually guided adaptive plasticity in the owl's auditory space map. 总被引:2,自引:0,他引:2
The midbrain contains an auditory map of space that is shaped by visual experience. When barn owls are raised wearing spectacles that horizontally displace the visual field, the auditory space map in the external nucleus of the inferior colliculus (ICX) shifts according to the optical displacement of the prisms. Topographic visual activity in the optic tectum could serve as the template that instructs the auditory space map. We studied the effects of a restricted, unilateral lesion in the portion of the optic tectum that represents frontal space. Here we show that such a lesion eliminates adaptive adjustments specifically in the portion of the auditory map that represents frontal space on the same side of the brain, while the rest of the map continues to adjust adaptively. Thus, activity in the tectum calibrates the auditory space map in a location-specific manner. Because the site of adaptive changes is the ICX, the results also indicate that the tectum provides a topographic instructive signal that controls adaptive auditory plasticity in the ICX. 相似文献
312.
Fibulin-5 is an elastin-binding protein essential for elastic fibre development in vivo. 总被引:16,自引:0,他引:16
Hiromi Yanagisawa Elaine C Davis Barry C Starcher Takashi Ouchi Masashi Yanagisawa James A Richardson Eric N Olson 《Nature》2002,415(6868):168-171
Extracellular elastic fibres provide mechanical elasticity to tissues and contribute towards the processes of organ remodelling by affecting cell-cell signalling. The formation of elastic fibres requires the assembly and crosslinking of tropoelastin monomers, and organization of the resulting insoluble elastin matrix into functional fibres. The molecules and mechanisms involved in this process are unknown. Fibulin-5 (also known as EVEC/DANCE) is an extracellular matrix protein abundantly expressed in great vessels and cardiac valves during embryogenesis, and in many adult tissues including the aorta, lung, uterus and skin, all of which contain abundant elastic fibres. Here we show that fibulin-5 is a calcium-dependent, elastin-binding protein that localizes to the surface of elastic fibres in vivo. fibulin-5-/- mice develop marked elastinopathy owing to the disorganization of elastic fibres, with resulting loose skin, vascular abnormalities and emphysematous lung. This phenotype, which resembles the cutis laxa syndrome in humans, reveals a critical function for fibulin-5 as a scaffold protein that organizes and links elastic fibres to cells. This function may be mediated by the RGD motif in fibulin-5, which binds to cell surface integrins, and the Ca2+-binding epidermal growth factor (EGF) repeats, which bind elastin. 相似文献
313.
Eric C. Xu 《天津科技大学学报》2004,19(Z1)
INTRODUCTIONIn papermaking, it is very often that more than one type (or grade) of pulps are used to develop paper sheet properties necessary for both machine runnability and requirement from the end users. In many high end paper grades (e.g., various high brightness printing/writing papers), long fiber from softwood bleached kraft pulp traditionally is often used in combination with short fiber from hardwood bleached kraft pulp (HBKP). In this combination, the long fiber component provi… 相似文献
314.
Morin RD Mendez-Lago M Mungall AJ Goya R Mungall KL Corbett RD Johnson NA Severson TM Chiu R Field M Jackman S Krzywinski M Scott DW Trinh DL Tamura-Wells J Li S Firme MR Rogic S Griffith M Chan S Yakovenko O Meyer IM Zhao EY Smailus D Moksa M Chittaranjan S Rimsza L Brooks-Wilson A Spinelli JJ Ben-Neriah S Meissner B Woolcock B Boyle M McDonald H Tam A Zhao Y Delaney A Zeng T Tse K Butterfield Y Birol I Holt R Schein J Horsman DE Moore R Jones SJ Connors JM Hirst M Gascoyne RD Marra MA 《Nature》2011,476(7360):298-303
Follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) are the two most common non-Hodgkin lymphomas (NHLs). Here we sequenced tumour and matched normal DNA from 13 DLBCL cases and one FL case to identify genes with mutations in B-cell NHL. We analysed RNA-seq data from these and another 113 NHLs to identify genes with candidate mutations, and then re-sequenced tumour and matched normal DNA from these cases to confirm 109 genes with multiple somatic mutations. Genes with roles in histone modification were frequent targets of somatic mutation. For example, 32% of DLBCL and 89% of FL cases had somatic mutations in MLL2, which encodes a histone methyltransferase, and 11.4% and 13.4% of DLBCL and FL cases, respectively, had mutations in MEF2B, a calcium-regulated gene that cooperates with CREBBP and EP300 in acetylating histones. Our analysis suggests a previously unappreciated disruption of chromatin biology in lymphomagenesis. 相似文献
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Grbić M Van Leeuwen T Clark RM Rombauts S Rouzé P Grbić V Osborne EJ Dermauw W Ngoc PC Ortego F Hernández-Crespo P Diaz I Martinez M Navajas M Sucena É Magalhães S Nagy L Pace RM Djuranović S Smagghe G Iga M Christiaens O Veenstra JA Ewer J Villalobos RM Hutter JL Hudson SD Velez M Yi SV Zeng J Pires-daSilva A Roch F Cazaux M Navarro M Zhurov V Acevedo G Bjelica A Fawcett JA Bonnet E Martens C Baele G Wissler L Sanchez-Rodriguez A Tirry L Blais C Demeestere K Henz SR Gregory TR Mathieu J 《Nature》2011,479(7374):487-492
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The sequence of the human genome has dramatically accelerated biomedical research. Here I explore its impact, in the decade since its publication, on our understanding of the biological functions encoded in the genome, on the biological basis of inherited diseases and cancer, and on the evolution and history of the human species. I also discuss the road ahead in fulfilling the promise of genomics for medicine. 相似文献