本帖最后由 细胞海洋 于 2011-2-24 19:40 编辑 0 b" t) ~, D. L5 q, N2 m4 F B# z) ]" {. y- {0 C4 M8 e$ A: w4 h
1. Title: Oct4 kinetics predict cell lineage patterning in the early mammalian embryo : J4 o, @3 f; G7 G# q* g# O2. 中文摘要:OCT4动态变化决定早期哺乳动物胚胎中细胞谱系发生; n4 X. |& K7 @
3. Abstract: Transcription factors are central to sustaining pluripotency, yet little is known about transcription factor dynamics in defining pluripotency in the early mammalian embryo. Here, we establish a fluorescence decay after photoactivation (FDAP) assay to quantitatively study the kinetic behaviour of Oct4, a key transcription factor controlling pre-implantation development in the mouse embryo. FDAP measurements reveal that each cell in a developing embryo shows one of two distinct Oct4 kinetics, before there are any morphologically distinguishable differences or outward signs of lineage patterning. The differences revealed by FDAP are due to differences in the accessibility of Oct4 to its DNA binding sites in the nucleus. Lineage tracing of the cells in the two distinct sub-populations demonstrates that the Oct4 kinetics predict lineages of the early embryo. Cells with slower Oct4 kinetics are more likely to give rise to the pluripotent cell lineage that contributes to the inner cell mass. Those with faster Oct4 kinetics contribute mostly to the extra-embryonic lineage. Our findings identify Oct4 kinetics, rather than differences in total transcription factor expression levels, as a predictive measure of developmental cell lineage patterning in the early mouse embryo.9 e' u- X3 w% I( P; ?
4. 标题: OCT4动态决定早期哺乳动物胚胎发育细胞谱系发生 1 k" Z" {# C7 b. Z* M9 B: I5 Y5. 摘要: 转录因子在维持细胞全能性起中心作用,但是到目前为止, 科学界对在早期胚胎中转录因子的动态所知甚少. OCT4是一个在小鼠胚胎发育过程中控制着床前阶段发育的一个核心的转录因子.在这里,我们建立了一个光子激发-荧光衰减(FDAP)技术来量化OCT4的动态变化. 通过FDAP,我们发现,OCT4的动态一共存在两种模式.在胚胎出现可以辨别的形态变化或者谱系形成之前, 发育中的胚胎内每个独立细胞只表现出一种OCT4动态模式.这种通过FDAP检测出的OTC动态差别是来源于OCT4是否可以在细胞核中与相应的DNA序列结合.通过对这两种表现不同OCT4动态的细胞的谱系追踪,我们发现OCT4的动态决定了早期胚胎的谱系(发生).那些具有较慢的OCT4动态的细胞,在发育过程中,最大可能地生成具备多能性的细胞谱系,并发育成为内细胞团.而具有较快速的OCT4动态变化的细胞,最后大都发育成生物胚胎外的细胞谱系.我们的结果揭示了OCT4的动态变化,而不是总的转录因子的表达水平,可以用来预测早期小鼠胚胎发育过程中不同细胞谱系的形成.! Q! T4 [/ k7 c6 }2 K" D- y
6. 下载链接: http://www.nature.com/ncb/journal/v13/n2/abs/ncb2154.html- f6 [$ i t7 n( R5 @. c
7. 备注:个人翻译,如有错误(或不准确)之处,敬请指出! 谢谢!/ z$ j4 I- g8 d
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1. Title: Oct4 kinetics predict cell lineage patterning in the early mammalian embryo 8 e; o- ], ^+ S# c* q2. 中文摘要:OCT4动态变化决定早期哺乳动物胚胎中细胞谱系发生$ a8 n5 E/ L# S8 z- R0 B" s
kinetics这里翻译为“动态变化”字面上没问题，不过这里指的是与转录因子表达“水平”“高低”不同的“动力学”特征——“快”与“慢”。这两类都可以称为“动态变化”，因此有可能引起误解。不妨花点力气，直接翻译为“动力学特征”。“决定”一词不符文意，应该是“预测”。 ' k9 J! k1 k# m3 I; l- \# ~ E" C4 a0 D4 p5 K3. Abstract: Transcription factors are central to sustaining pluripotency, yet little is known about transcription factor dynamics in defining pluripotency in the early mammalian embryo. Here, we establish a fluorescence decay after photoactivation (FDAP) assay to quantitatively study the kinetic behaviour of Oct4, a key transcription factor controlling pre-implantation development in the mouse embryo. FDAP measurements reveal that each cell in a developing embryo shows one of two distinct Oct4 kinetics, before there are any morphologically distinguishable differences or outward signs of lineage patterning. The differences revealed by FDAP are due to differences in the accessibility of Oct4 to its DNA binding sites in the nucleus. Lineage tracing of the cells in the two distinct sub-populations demonstrates that the Oct4 kinetics predict lineages of the early embryo. Cells with slower Oct4 kinetics are more likely to give rise to the pluripotent cell lineage that contributes to the inner cell mass. Those with faster Oct4 kinetics contribute mostly to the extra-embryonic lineage. Our findings identify Oct4 kinetics, rather than differences in total transcription factor expression levels, as a predictive measure of developmental cell lineage patterning in the early mouse embryo.' L/ k0 x( w0 {: q1 D% K2 E
4. 标题: OCT4动态决定早期哺乳动物胚胎发育细胞谱系发生 ( `: |: M$ A4 W0 t摘要: 转录因子在维持细胞全能性起中心作用,但是到目前为止, 科学界对在早期胚胎中转录因子的动态所知甚少. OCT4是一个在小鼠胚胎发育过程中控制着床前阶段发育的一个核心的转录因子.在这里,我们建立了一个光子激发-荧光衰减(FDAP)技术来量化OCT4的动态变化. 通过FDAP,我们发现,OCT4的动态一共存在两种模式.在胚胎出现可以辨别的形态变化或者谱系形成之前, 发育中的胚胎内每个独立细胞只表现出一种OCT4动态模式.: [, y$ H7 n9 Y3 w
FDAP检测揭示出，发育过程中的胚胎在尚未出现可辨别的形态变化或谱系形成的外在征兆之前，其中的每一个细胞均表现出两种独特的Oct4动力特征之一。! U) M3 K: Z! Y- @5 y# n
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感谢提供原文。 3 B0 b H+ r% O$ H- N; k& i4 s 8 }# a' |6 `2 M# M% @$ f' A) \It will be important to assess in the future whether and how the distinct Oct4–paGFP kinetics reported here relate to previous demonstrations of cell heterogeneity in the early embryo. These include, for example, the order and orientation of cell divisions2 and the levels of proteins involved in epigenetic modifications7, which have been described at the 4-cell stage, as well as the subcellular distribution of the transcription factor Cdx2 (ref. 5).9 P3 D8 |: q' [: y8 W