Thursday, 31 January, 2013
The importance of the envelope
In a project that began with the retinal cells of nocturnal animals and has led to fundamental insights into the organization of genomic DNA, LMU researchers show how the nuclear envelope affects nuclear architecture - and gene regulation.
The double-stranded DNA molecules that make up the genetic material are wrapped around protein complexes to form compacted “chromatin”. The active portion of the genome is less densely packed, and thus more easily accessible, than the inactive fraction, and is referred to as euchromatin. Euchromatin is typically located in the inner regions of the cell nucleus, while much of the inactive DNA in “heterochromatin” is associated with the inner face of the nuclear envelope. This type of chromatin organization is found in almost all higher organisms and may have been invented 500 million years ago.