X-inactivation - Wikipedia
X-inactivation (also called Lyonization, after English geneticist Mary Lyon) is a process by which one of the copies of the X chromosome is inactivated in therian female mammals. The inactive X chromosome is silenced by being packaged into a transcriptionally inactive structure called heterochromatin.
X-inactivation (article) | Khan Academy
X-inactivation is a random process that happens separately in individual cells during embryonic development. One cell might shut down the paternal X, while its next-door neighbor might shut down the maternal X instead.
X Chromosome Inactivation | Learn Science at Scitable - Nature
X inactivation only occurs in cells with multiple X chromosomes, which explains why almost all calico cats are female. X inactivation exists in two different forms: random and imprinted.
3.3: X-inactivation - Biology LibreTexts
2021年12月14日 · In X-inactivation, an X chromosome is compacted (or, as my intro bio professor liked to say, "crumpled up into a ball"), to make a small, dense structure called a Barr body. Most of the genes on the Barr body are inactive, meaning that they are not transcribed.
Lyonization - National Human Genome Research Institute
2 天之前 · Lyonization (also called X-inactivation) refers to the normal phenomenon in which one of the two X chromosomes in every cell of a female individual is inactivated during embryonic development.
Mechanisms of Choice in X-Chromosome Inactivation - PMC
For placental mammals with two X chromosomes, another critical moment in their lives is when, in each of their cells, one of their X chromosomes becomes inactivated. This choice, and the patterns of gene expression that derive from it, can have significant implications.
X Inactivation and Escape: Epigenetic and Structural Features
2019年10月1日 · A subset of genes escapes X inactivation, raising questions about mechanisms that preserve their expression despite being embedded within heterochromatin. Escape gene expression differs between males and females, which can lead to physiological sex differences.
X-chromosome inactivation and escape - PMC - National Center …
X-chromosome inactivation, which was discovered by Mary Lyon in 1961 results in random silencing of one X chromosome in female mammals. This review is dedicated to Mary Lyon, who passed away last year.
X-chromosome inactivation: the gift that keeps on giving
2023年8月18日 · Inactivation of the X chromosome, also known as lyonization, occurs randomly, resulting in a unique mosaic of fur coat colors.
Landscape of X chromosome inactivation across human tissues
2017年10月12日 · X chromosome inactivation (XCI) silences transcription from one of the two X chromosomes in female mammalian cells to balance expression dosage between XX females and XY males.