Lamin B locks up Oct-1

Jan 12, 2009

A large fraction of the transcription factor Oct-1 is associated with the inner nuclear envelope, but how and why it is retained there was unknown.

As for how, Malhas et al. show—in the January 12, 2009 issue of the Journal of Cell Biology (www.jcb.org)—that Oct-1 binds to lamin B1, a prominent intermediate filament that lines the nuclear envelope, and in cells expressing a drastically truncated mutant of lamin B1, Oct-1 was disassociated from the nuclear envelope.

This left the question, why? The authors asked whether disrupting lamin B1-Oct-1 interactions could affect the expression of genes regulated by Oct-1. Indeed, in cells with truncated lamin B1, they found that expression of several Oct-1-regulated genes was altered because more Oct-1 could bind at these genes' promoters. Among the genes was a group involved in the oxidative stress response. As a result, these mutant cells accumulated higher levels of reactive oxygen species than wild-type cells.

It remains to be seen whether and how lamin B1-Oct-1 interactions are actively regulated in cells to help control gene expression. But, it is evident from these results that perturbation of lamin B1-Oct-1 interactions can make cells more vulnerable to oxidative stress. This could be particularly important in aging cells, where nuclear envelope integrity (and lamin B1 localization) is often perturbed, says author David Vaux. Lamins support the structure of the nucleus, and compromised nuclear structure has been a suspected cause of aging; another type of lamin, lamin A, is known to cause a premature aging disease when faulty. Increased production of reactive oxygen species—due to the perturbation of lamin B1 in mature cells—could be another way in which lamins contribute to the aging process.

Source: Rockefeller University

Explore further: 'Tiger heavyweight' Nepal hosts anti-poaching summit

add to favorites email to friend print save as pdf

Related Stories

Cell nuclei harbor factories that transcribe genes

Sep 27, 2013

Our genetic heritage is contained—and protected—in the nucleus of the cells that compose us. Copies of the DNA exit the nucleus to be read and translated into proteins in the cell cytoplasm. The transit between the nucleus ...

Programming cells: The importance of the envelope

Feb 01, 2013

In a project that began with the retinal cells of nocturnal animals and has led to fundamental insights into the organization of genomic DNA, researchers from Ludwig-Maximilians-Universitaet (LMU) in Munich show how the nuclear ...

Recommended for you

'Tiger heavyweight' Nepal hosts anti-poaching summit

5 hours ago

Nepal's success in turning tiger-fearing villagers into their protectors has seen none of the endangered cats killed for almost three years, offering key lessons for an anti-poaching summit opening in Kathmandu ...

GMO mosquito plan sparks outcry in Florida

Jan 31, 2015

A British company's plan to unleash hordes of genetically modified mosquitoes in Florida to reduce the threat of dengue fever and other diseases has sparked an outcry from fearful residents.

Population genomics unveil seahorse domain

Jan 30, 2015

In a finding vital to effective species management, a team including City College of New York biologists has determined that the lined seahorse (Hippocampus erectus) is more a permanent resident of the we ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.