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141.
142.
Grant J Mahadevaiah SK Khil P Sangrithi MN Royo H Duckworth J McCarrey JR VandeBerg JL Renfree MB Taylor W Elgar G Camerini-Otero RD Gilchrist MJ Turner JM 《Nature》2012,487(7406):254-258
In female (XX) mammals, one of the two X chromosomes is inactivated to ensure an equal dose of X-linked genes with males (XY). X-chromosome inactivation in eutherian mammals is mediated by the non-coding RNA Xist. Xist is not found in metatherians (marsupials), and how X-chromosome inactivation is initiated in these mammals has been the subject of speculation for decades. Using the marsupial Monodelphis domestica, here we identify Rsx (RNA-on-the-silent X), an RNA that has properties consistent with a role in X-chromosome inactivation. Rsx is a large, repeat-rich RNA that is expressed only in females and is transcribed from, and coats, the inactive X chromosome. In female germ cells, in which both X chromosomes are active, Rsx is silenced, linking Rsx expression to X-chromosome inactivation and reactivation. Integration of an Rsx transgene on an autosome in mouse embryonic stem cells leads to gene silencing in cis. Our findings permit comparative studies of X-chromosome inactivation in mammals and pose questions about the mechanisms by which X-chromosome inactivation is achieved in eutherians. 相似文献
143.
Enzyme mechanism of aminoacetone metabolism by micro-organisms 总被引:6,自引:0,他引:6
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R. J. Turner 《Cellular and molecular life sciences : CMLS》1972,28(3):370-371
Riassunto Il riconoscimento e la localizzazione di cellule del reticolo-endotelio, che fagocitano particelle di carbone, può talora essere difficile impiegando la convenzionale microscopia a luce trasmessa su sezioni istologiche colorante o in presenza di pigmento. D'altro canto, le particelle carboniose sono facilmente distinguibili impiegando la luce incidente, che e'riflessa de queste, ma non dalle cellule o da granuli di pigmento.
This work was carried out during tenure of a Science Research Council studentship at the Zoology Department, University of Hull, England. The author is indebted to Dr.M. J. Manning for her helpful advice and criticism. 相似文献
This work was carried out during tenure of a Science Research Council studentship at the Zoology Department, University of Hull, England. The author is indebted to Dr.M. J. Manning for her helpful advice and criticism. 相似文献
146.
Summary Adenylate cyclase responses of brain cortex and neostriatum to noradrenaline and dopamine are increased in rats with jaundice in proportion to its severity. In comparing the situation with uraemia, the relevance of phenols has to be considered. 相似文献
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149.
Silent allele as genetic basis of fucosidosis. 总被引:4,自引:0,他引:4
150.
G. A. Turner 《Cellular and molecular life sciences : CMLS》1979,35(12):1657-1658
Summary The ability of collagenase to disaggregate a solid metastasizing lymphosarcoma has been shown to considerably increase with reducing environmental pH. It is suggested that this effect may be operating in vivo to release cells from a primary tumour. 相似文献