Foreword: Coping with sex chromosome imbalance.
Foreword: Coping with sex chromosome imbalance.
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前言：应对性染色体失衡。
DOI：
10.1007/s10577-009-9062-x
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Carrel,Laura
中科院分区：
文献类型：
--
作者：
Heard,Edith;Carrel,Laura
本期特刊专门讨论剂量补偿这一主题。与大多数常染色体单体或三体相关的显着表型说明了在二倍体生物中维持适当基因剂量的重要性。缓冲和补偿这种遗传失衡显然对复杂的真核生物来说是一个挑战。在具有基于染色体的性别决定机制（XX/XY和ZW/ZZ）的性二态性物种中，雄性和雌性中性染色体的对比剂量预计会导致基因表达水平的大规模失衡。这种不平衡存在于两个层面。首先，性别之间的剂量差异（XX 与 XY 或 ZW 与 ZZ）；其次，异配性别（XY 男性或 ZW 女性）中性染色体和常染色体之间的剂量差异，其中仅存在单个 X 或 Z 染色体拷贝，而所有常染色体都有两个拷贝。然而，性染色体失衡通常可以很好地耐受 - 这是怎么回事？现在已经清楚，在许多生物体中，来自祖先常染色体对的性染色体的进化必定伴随着剂量补偿策略的进化，以平衡雄性和雌性中与性别相关的基因表达。几十年前首次注意到此类策略的存在。 1932 年，Muller 首次针对黑腹果蝇提出了这个问题。 1967年，大野预测“……在进化过程中，胎盘哺乳动物的祖先一定通过使每个X连锁基因的产物产出率加倍而逃脱了雄性中所有X连锁基因的半合子存在所带来的危险”。现在很清楚，上调雄性 X 染色体以达到与常染色体相当的水平是在线虫、果蝇和哺乳动物中发现的一种进化保守策略。 1961 年，Mary Lyon 发表了她的开创性论文，概述了哺乳动物 X 染色体失活的过程，通过早期发育过程中雌性两条 X 染色体之一的沉默和异染色质化，可以实现两性之间 X 连锁基因剂量的等效。随后在具有 XY/XX 二态性染色体的其他生物体中发现了许多剂量补偿策略的替代策略。在果蝇中，X 染色体的上调仅发生在雄性中，因此一举解决了性别特异性和 X 常染色体剂量问题。在
This special issue is devoted to the topic of dosage compensation. The dramatic phenotypes that are associated with most autosomal monosomies or trisomies illustrate the importance of maintaining appropriate gene dosage in diploid organisms. Buffering and compensating for such genetic imbalance clearly represents a challenge for complex eukaryotes. In sexually dimorphic species with chromosomebased mechanisms of sex determination (XX/XY and ZW/ZZ), the contrasting doses of sex chromosomes in males and females would be expected to introduce a large-scale imbalance in levels of gene expression. This imbalance would be at two levels. First, the dosage differences between the sexes (XX versus XY or ZW versus ZZ); second, the dosage difference between sex chromosomes and autosomes in the heterogametic sex (XY males, or ZW females) where only a single copy of the X or Z chromosome is present, in contrast to two copies of all autosomes.However, sex chromosome imbalances are usually well tolerated—how can this be? It is now clear that in many organisms the evolution of sex chromosomes from an ancestral autosome pair must have been accompanied by the evolution of dosage compensation strategies, in order to equalize sex-linked gene expression in males and females. The existence of such strategies was first noted many decades ago. In 1932, the issue was first raised for D. melanogaster by Muller. In 1967, Ohno predicted that “… during the course of evolution, an ancestor to placental mammals must have escaped a peril resulting from the hemizygous existence of all the X-linked genes in the male by doubling the rate of product output of each X-linked gene”. It is now clear that up-regulation of the male X chromosome to achieve equivalent levels to autosomes is an evolutionarily conserved strategy found in worms, flies and mammals. In 1961 Mary Lyon published her seminal paper, outlining the process of X-chromosome inactivation in mammals, that enables equivalence of X-linked gene dosage between the sexes to be obtained through the silencing and heterochromatinization of one of the two X chromosomes in females during early development. Numerous alternative strategies of dosage compensation strategies were subsequently discovered in other organisms with XY/XX dimorphic sex chromosomes. In flies up-regulation of the X chromosome occurs only in males, thus dealing with both the sex-specific and X-autosomal dosage problems in one fell swoop. In
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影响因子：
64.8
作者：
COOPER, DW
通讯作者：
COOPER, DW
X 连锁 HMG-lacZ 转基因在小鼠胚胎中的表达：染色体印记和谱系特异性 X 染色体活性的含义。
DOI：
10.1002/dvg.1020150608
发表时间：
1994
期刊：
Developmental genetics
影响因子：
--
作者：
P. Tam;E. Williams;S. Tan
通讯作者：
S. Tan
转基因小鼠胚胎中父本 Pgk-1 表达的时间。
DOI：
10.1242/dev.111.4.1109
发表时间：
1991
期刊：
Development (Cambridge, England)
影响因子：
--
作者：
Pravtcheva,DD;Adra,CN;Ruddle,FH
通讯作者：
Ruddle,FH
影响因子：
4
作者：
James M. A. Turner;S. Mahadevaiah;D. Elliott;H. Garchon;J. Pehrson;R. Jaenisch;P. Burgoyne
通讯作者：
James M. A. Turner;S. Mahadevaiah;D. Elliott;H. Garchon;J. Pehrson;R. Jaenisch;P. Burgoyne
影响因子：
7.5
作者：
Huynh, KD;Lee, JT
通讯作者：
Lee, JT