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Morison IM Cramer Bordé EM Cheesman EJ Cheong PL Holyoake AJ Fichelson S Weeks RJ Lo A Davies SM Wilbanks SM Fagerlund RD Ludgate MW da Silva Tatley FM Coker MS Bockett NA Hughes G Pippig DA Smith MP Capron C Ledgerwood EC 《Nature genetics》2008,40(4):387-389
We report the first identified mutation in the gene encoding human cytochrome c (CYCS). Glycine 41, invariant throughout eukaryotes, is substituted by serine in a family with autosomal dominant thrombocytopenia caused by dysregulated platelet formation. The mutation yields a cytochrome c variant with enhanced apoptotic activity in vitro. Notably, the family has no other phenotypic indication of abnormal apoptosis, implying that cytochrome c activity is not a critical regulator of most physiological apoptosis. 相似文献
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Electric polarization reversal and memory in a multiferroic material induced by magnetic fields 总被引:1,自引:0,他引:1
Ferroelectric and magnetic materials are a time-honoured subject of study and have led to some of the most important technological advances to date. Magnetism and ferroelectricity are involved with local spins and off-centre structural distortions, respectively. These two seemingly unrelated phenomena can coexist in certain unusual materials, termed multiferroics. Despite the possible coexistence of ferroelectricity and magnetism, a pronounced interplay between these properties has rarely been observed. This has prevented the realization of multiferroic devices offering such functionality. Here, we report a striking interplay between ferroelectricity and magnetism in the multiferroic TbMn2O5, demonstrated by a highly reproducible electric polarization reversal and permanent polarization imprint that are both actuated by an applied magnetic field. Our results point to new device applications such as magnetically recorded ferroelectric memory. 相似文献
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Watanabe H Fujiyama A Hattori M Taylor TD Toyoda A Kuroki Y Noguchi H BenKahla A Lehrach H Sudbrak R Kube M Taenzer S Galgoczy P Platzer M Scharfe M Nordsiek G Blöcker H Hellmann I Khaitovich P Pääbo S Reinhardt R Zheng HJ Zhang XL Zhu GF Wang BF Fu G Ren SX Zhao GP Chen Z Lee YS Cheong JE Choi SH Wu KM Liu TT Hsiao KJ Tsai SF Kim CG OOta S Kitano T Kohara Y Saitou N Park HS Wang SY Yaspo ML Sakaki Y 《Nature》2004,429(6990):382-388
Human-chimpanzee comparative genome research is essential for narrowing down genetic changes involved in the acquisition of unique human features, such as highly developed cognitive functions, bipedalism or the use of complex language. Here, we report the high-quality DNA sequence of 33.3 megabases of chimpanzee chromosome 22. By comparing the whole sequence with the human counterpart, chromosome 21, we found that 1.44% of the chromosome consists of single-base substitutions in addition to nearly 68,000 insertions or deletions. These differences are sufficient to generate changes in most of the proteins. Indeed, 83% of the 231 coding sequences, including functionally important genes, show differences at the amino acid sequence level. Furthermore, we demonstrate different expansion of particular subfamilies of retrotransposons between the lineages, suggesting different impacts of retrotranspositions on human and chimpanzee evolution. The genomic changes after speciation and their biological consequences seem more complex than originally hypothesized. 相似文献
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Multiple phosphoglucomutase (E.C.2.7.5.1) alleles are found in the mosquitoes Mansonia crassipes and M. uniformis. The present study reveals 4 Pgm alleles, of which Pgm(B) and Pgm(C) are common to both species while Pgm(A) is present only in M. crassipes and Pgm(D) only in M uniformis. The frequencies in both species accord well with Hardy-Weinberg expectations. The most frequent allele is that controlling a phenotype with an intermediate electrophoretic mobility, viz Pgm(B) in M. crassipes and Pgm(C) in M. Uniformis. 相似文献