Nuclear organization

thumb|Basic units of chromatin structure

Heterochromatin is a tightly packed form of chromatin, which comes in multiple varieties. These varieties lie on a continuum between the two extremes of constitutive heterochromatin and facultative heterochromatin. Both play a role in the expression of genes, and correlate with late replication timing. Importantly, heterochromatin was once thought to be tightly coupled with structural compactness, phase separation and also deterministic transcriptional silencing. However, these notions have been increasingly challenged in recent years.

genetic testing technique

thumb|300x300px|Distinction between Euchromatin and Heterochromatin Euchromatin (also called "open chromatin") is a lightly packed form of chromatin (DNA, RNA, and protein) that is enriched in genes, and is often (but not always) under active transcription. Euchromatin stands in contrast to heterochromatin, which is tightly packed and less accessible for transcription. 92% of the human genome is euchromatic.

thumb|Diagram of cohesin showing its four constituent protein subunits

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

set of molecular biology methods used to analyze the spatial organization of chromatin in a cell

Transcriptional repressor CTCF also known as 11-zinc finger protein or CCCTC-binding factor is a transcription factor that in humans is encoded by the CTCF gene. CTCF is involved in many cellular processes, including transcriptional regulation, insulator activity, V(D)J recombination and regulation of chromatin architecture.

family of proteins that play a role in chromatin remodeling

self-interacting genomic region

regions of the nucleus preferentially occupied by particular chromosomes