CTCF Regulates Asynchronous Replication of the Imprinted H19/Igf2 Domain

Chromosome replication has been analysed in four species of Chilocorus. In C. orbus Csy., C. tricyclus Smith, and C. hexacyclus Smith, centric regions of all chromosomes are last to replicate, preceded in order by heterochromatic arms and euchromatic arms. In C. stigma Say, very late replication of centric regions can be detected only in otherwise wholly euchromatic chromosomes (= monophasics); in chromosomes with one arm heterochromatic (= diphasics), these arms are last to replicate. Based on pachytene bivalent morphology and chromosome banding patterns, and supported by autoradiographic data, models are presented for the general organisation of Chilocorus chromosomes. All chromosomes in the first three species are subdivided into euchromatic arm, centric heterochromatin, and either a second euchromatic arm (monophasics) or a heterochromatic arm (diphasics). Chilocorus stigma diphasics apparently lack distinct centric organisation, and are therefore divided into euchromatic and heterochromatic arms only.

Download Full-text

cis preferential replication of Lettuce infectious yellows virus (LIYV) RNA 1: The initial step in the asynchronous replication of the LIYV genomic RNAs

Virology ◽

10.1016/j.virol.2009.01.004 ◽

2009 ◽

Vol 386 (1) ◽

pp. 217-223 ◽

Cited By ~ 14

Author(s):

Jinbo Wang ◽

Hsin-Hung Yeh ◽

Bryce W. Falk

Keyword(s):

Initial Step ◽

Genomic Rnas ◽

Asynchronous Replication ◽

Lettuce Infectious Yellows Virus

Download Full-text

Asynchronous replication of allelic loci in Down syndrome

European Journal of Human Genetics ◽

10.1038/sj.ejhg.5200199 ◽

1998 ◽

Vol 6 (4) ◽

pp. 359-364 ◽

Cited By ~ 22

Author(s):

Aliza Amiel ◽

Lydia Avivi ◽

Elena Gaber ◽

Moshe D Fejgin

Keyword(s):

Down Syndrome ◽

Asynchronous Replication

Download Full-text

X chromosome choice occurs independently of asynchronous replication timing

The Journal of Cell Biology ◽

10.1083/jcb.200405117 ◽

2005 ◽

Vol 168 (3) ◽

pp. 365-373 ◽

Cited By ~ 29

Author(s):

Joost Gribnau ◽

Sandra Luikenhuis ◽

Konrad Hochedlinger ◽

Kim Monkhorst ◽

Rudolf Jaenisch

Keyword(s):

X Chromosome ◽

Molecular Mechanisms ◽

Replication Timing ◽

S Phase ◽

X Inactivation ◽

Wild Type ◽

Gene Deletions ◽

Asynchronous Replication ◽

Skewed X Inactivation

In mammals, dosage compensation is achieved by X chromosome inactivation in female cells. Xist is required and sufficient for X inactivation, and Xist gene deletions result in completely skewed X inactivation. In this work, we analyzed skewing of X inactivation in mice with an Xist deletion encompassing sequence 5 KB upstream of the promoter through exon 3. We found that this mutation results in primary nonrandom X inactivation in which the wild-type X chromosome is always chosen for inactivation. To understand the molecular mechanisms that affect choice, we analyzed the role of replication timing in X inactivation choice. We found that the two Xist alleles and all regions tested on the X chromosome replicate asynchronously before the start of X inactivation. However, analysis of replication timing in cell lines with skewed X inactivation showed no preference for one of the two Xist alleles to replicate early in S-phase before the onset of X inactivation, indicating that asynchronous replication timing does not play a role in skewing of X inactivation.

Download Full-text