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61.
FGFR-related gene nou-darake restricts brain tissues to the head region of planarians 总被引:7,自引:0,他引:7
Cebrià F Kobayashi C Umesono Y Nakazawa M Mineta K Ikeo K Gojobori T Itoh M Taira M Sánchez Alvarado A Agata K 《Nature》2002,419(6907):620-624
The study of planarian regeneration may help us to understand how we can rebuild organs and tissues after injury, disease or ageing. The robust regenerative abilities of planarians are based upon a population of totipotent stem cells (neoblasts), and among the organs regenerated by these animals is a well-organized central nervous system. In recent years, methodologies such as whole-mount in situ hybridizations and double-stranded RNA have been extended to planarians with the aim of unravelling the molecular basis of their regenerative capacities. Here we report the identification and characterization of nou-darake (ndk), a gene encoding a fibroblast growth factor receptor (FGFR)-like molecule specifically expressed in the head region of the planarian Dugesia japonica. Loss of function of ndk by RNA interference results in the induction of ectopic brain tissues throughout the body. This ectopic brain formation was suppressed by inhibition of two planarian FGFR homologues (FGFR1 and FGFR2). Additionally, ndk inhibits FGF signalling in Xenopus embryos. The data suggest that ndk may modulate FGF signalling in stem cells to restrict brain tissues to the head region of planarians. 相似文献
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Ota T Suzuki Y Nishikawa T Otsuki T Sugiyama T Irie R Wakamatsu A Hayashi K Sato H Nagai K Kimura K Makita H Sekine M Obayashi M Nishi T Shibahara T Tanaka T Ishii S Yamamoto J Saito K Kawai Y Isono Y Nakamura Y Nagahari K Murakami K Yasuda T Iwayanagi T Wagatsuma M Shiratori A Sudo H Hosoiri T Kaku Y Kodaira H Kondo H Sugawara M Takahashi M Kanda K Yokoi T Furuya T Kikkawa E Omura Y Abe K Kamihara K Katsuta N Sato K Tanikawa M Yamazaki M Ninomiya K Ishibashi T Yamashita H Murakawa K Fujimori K 《Nature genetics》2004,36(1):40-45
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The origin and evolution of the Moon remain controversial, with one of the most important questions for lunar evolution being the timing and duration of basaltic (mare) magmatism. Here we report the result of ion microprobe U-Pb dating of phosphates in a lunar meteorite, Kalahari 009, which is classified as a very-low-Ti mare-basalt breccia. In situ analyses of five phosphate grains, associated with basaltic clasts, give an age of 4.35 +/- 0.15 billion years. These ancient phosphate ages are thought to represent the crystallization ages of parental basalt magma, making Kalahari 009 one of the oldest known mare basalts. We suggest that mare basalt volcanism on the Moon started as early as 4.35 Gyr ago, relatively soon after its formation and differentiation, and preceding the bulk of lunar volcanism which ensued after the late heavy bombardment around 3.8-3.9 Gyr (refs 7 and 8). Considering the extremely low abundances of incompatible elements such as thorium and the rare earth elements in Kalahari 009 (ref. 9) and recent remote-sensing observations illustrating that the cryptomaria tend to be of very-low-Ti basalt type, we conclude that Kalahari 009 is our first sample of a very-low-Ti cryptomare from the Moon. 相似文献
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S Tachibana SA Sullivan S Kawai S Nakamura HR Kim N Goto N Arisue NM Palacpac H Honma M Yagi T Tougan Y Katakai O Kaneko T Mita K Kita Y Yasutomi PL Sutton R Shakhbatyan T Horii T Yasunaga JW Barnwell AA Escalante JM Carlton K Tanabe 《Nature genetics》2012,44(9):1051-1055
P. cynomolgi, a malaria-causing parasite of Asian Old World monkeys, is the sister taxon of P. vivax, the most prevalent malaria-causing species in humans outside of Africa. Because P. cynomolgi shares many phenotypic, biological and genetic characteristics with P. vivax, we generated draft genome sequences for three P. cynomolgi strains and performed genomic analysis comparing them with the P. vivax genome, as well as with the genome of a third previously sequenced simian parasite, Plasmodium knowlesi. Here, we show that genomes of the monkey malaria clade can be characterized by copy-number variants (CNVs) in multigene families involved in evasion of the human immune system and invasion of host erythrocytes. We identify genome-wide SNPs, microsatellites and CNVs in the P. cynomolgi genome, providing a map of genetic variation that can be used to map parasite traits and study parasite populations. The sequencing of the P. cynomolgi genome is a critical step in developing a model system for P. vivax research and in counteracting the neglect of P. vivax. 相似文献
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M. Sano M. Terada A. I. Ishii H. Kino M. Anantaphruti 《Cellular and molecular life sciences : CMLS》1982,38(5):547-549
Summary Niclosamide, a well-known antitapeworm drug, caused spastic and/or paralytic actions on the motility of various preparations
including parasitic cestodes, trematodes, nematodes, and host isolated tissues. 相似文献
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