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 [...]

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 [...]

What is translation? Translation is a process that involves the synthesis of an amino acid chain from an mRNA blueprint. These polypeptide chains fold into functional proteins. Translation occurs outside the nucleus once nuclear processing of the pre-mRNA is complete and the mRNA molecules [...]

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’ [...]

How is transcription regulated in stem cells? Pluripotent stem cells can potentially differentiate into any given cell type. They commonly exhibit mechanically softer nuclei [1], lack type-A lamins [2] and have a poorly defined cytoskeleton [3][4]. Embryonic stem cells are pluripotent in early organism [...]

How is DNA replicated? Cells must replicate their DNA before they can divide. This ensures that each daughter cell gets a copy of the genome, and therefore, successful inheritance of genetic traits. DNA replication is an essential process and the basic mechanism is conserved [...]

What are telomeres? Telomeres are short nucleotide sequences found at the end of linear chromosomes which protect the genetic information. In vertebrates, telomeres have the hexameric sequence TTAGGG. During DNA replication, the double stranded DNA is unwound and DNA polymerase synthesizes new strands. However, [...]