Genome Regulation Genome regulation encompasses all facets of gene expression, from the biochemical modifications of DNA, to the physical arrangement of chromosomes and the activity of the transcription machinery. The genome regulation programs that cells engage control which proteins are produced, and to what [...]

What is the nucleus? The nucleus is an organelle found in most eukaryotic cells, the exception being red blood cells. In animal cells it is both the largest and stiffest organelle and is easily identifiable by light microscopy. The average mammalian nucleus has a [...]

What properties of the nucleus facilitate mechanotransduction? Similar to the concept of long distance force propagation along the cytoskeleton, the prestressed nuclear state, which counterbalances intracellular forces from the cytoskeleton, enables mechanotransduction [1][2]. Both the nuclear envelope and nuclear interior contribute to the mechanical [...]

How is nuclear “prestress” maintained? As an integral part of cellular behavior, cells are sensitive to matrix rigidity, local geometry and stress or strain applied by external factors [1]. In recent years, it has been established that an extensive network of protein assembly couples [...]

How is the nucleus coupled to the cytoskeleton? Cytoskeletal filaments bridge the nucleus to the plasma membrane, which in turn is anchored at sub-cellular sites to extracellular substrates via a plethora of proteins that form focal adhesions (FAs). FAs are points of cross-talk between [...]

What are nucleosomes? In order to fit DNA into the nucleus, it must be packaged into a highly compacted structure known as chromatin. In the first step of this process DNA is condensed into an 11 nm fiber that represents an approximate 6-fold level [...]

What is chromatin, heterochromatin and euchromatin? The human genome contains over 3 billion base pairs or nucleotides. These nucleotides, which are arranged in a linear sequence along DNA (deoxyribonucleic acid), encode every protein and genetic trait in the human body. This information is contained [...]

What are chromosomes and chromosome territories? While metaphase chromosomes can be depicted as distinct bodies with well-defined shapes and sizes, interphase chromosomes are less uniform and, by filling the nuclear space, difficult to distinguish. Despite this, recent research has revealed how the nuclear architecture [...]

How does chromatin condensation keep the nucleus compact? Packaging of approximately a meter-long DNA duplex within the elastic nucleus determines its spatial 3D architecture and the genomic accessibility of tissue-specific transcriptional programs. Apart from several biochemical processes, there are various forces at play in [...]

How do chromosome territory dynamics affect gene redistribution? The spatial organization of chromatin within the 3-dimensional space of a chromosome territory enables the co-localization of co-transcribed genes and their transcriptional foci. Many gene positioning studies have shown that individual genes often loop out of [...]

What are transcription factories? The primary role of chromatin assembly is the compaction of an otherwise very long DNA molecule into discrete structures that fit into the nucleus. However, this compaction cannot be achieved at the expense of a cells ability to transcribe and [...]

How does chromatin remodeling impact gene transcription? While chromosome territory dynamics is believed to regulate gene expression through the redistribution of genes and the subsequent co-localization of these genes with transcription machinery, changes are also commonly made to the chromosome structure at a ‘local’ [...]