Abstract
Assembly of the nuclear envelope (NE) in telophase is essential for higher eukaryotic cells to re-establish a functional nucleus. Time-lapse, FRAP and FRET analyses in human cells showed that barrier-to-autointegration factor (BAF), a DNA-binding protein, assembled first at the distinct ;core' region of the telophase chromosome and formed an immobile complex by directly binding with other core-localizing NE proteins, such as lamin A and emerin. Correlative light and electron microscopy after live cell imaging, further showed that BAF formed an electron-dense structure on the chromosome surface of the core, close to spindle microtubules (MTs) prior to the attachment of precursor NE membranes, suggesting that MTs may mediate core assembly of BAF. Disruption of the spindle MTs consistently abolished BAF accumulation at the core. In addition, RNAi of BAF eliminated the core assembly of lamin A and emerin, caused abnormal cytoplasmic accumulation of precursor nuclear membranes and resulted in a significant delay of NE assembly. These results suggest that the MT-mediated BAF accumulation at the core facilitates NE assembly at the end of mitosis.
Highlights
The nuclear envelope (NE) is a cellular structure that encloses chromosomes and provides a physicochemical framework for genetic activities such as gene expression and DNA replication
We found that emerin, LAP2β and lamin A accumulated in the core region during telophase in a barrier-to-autointegration factor (BAF)-dependent manner (Haraguchi et al, 2001)
BAF assembles first to thecoreregion of the reforming telophase nuclear envelope Assembly of NE proteins at the end of mitosis is an essential step in the reformation of a functional nucleus in higher eukaryotic cells
Summary
The nuclear envelope (NE) is a cellular structure that encloses chromosomes and provides a physicochemical framework for genetic activities such as gene expression and DNA replication. A variety of human disorders known as ‘nuclear envelopathy’ or ‘nuclear laminopathy’ have been reported (reviewed by Nagano and Arahata, 2000; Wilson et al, 2001; Worman and Courvalin, 2005). These disorders involve mutations in NE components. Mutations in the gene encoding lamin A (official protein symbol, LMNA) cause 12 human diseases (reviewed by Mattout et al, 2006) including Emery-Dreifuss muscular dystrophy (Bonne et al, 1999; Clements et al, 2000) and Hutchinson-Gilford progeria syndrome (Eriksson et al, 2003; Mounkes et al, 2003). Understanding the dynamic architecture of the NE will provide insight into the regulatory mechanisms for these cellular functions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
