In cell biology, chromosome territories are regions of the nucleus preferentially occupied by particular

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

Interphase Interphase is the portion of the cell cycle that is not accompanied by visible changes under the microscope, and includes the G1, S and G2 phases. During interphase, the cell grows (G1), replicates its DNA (S) and prepares for mitosis (G2). A c ...

chromosomes are long DNA strands that are extensively folded, and are often described as appearing like a bowl of

spaghetti Spaghetti () is a long, thin, solid, cylindrical pasta.spaghetti
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. The chromosome territory concept holds that despite this apparent disorder, chromosomes largely occupy defined regions of the nucleus. Most eukaryotes are thought to have chromosome territories, although the budding

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constit ...

'' S. cerevisiae'' is an exception to this.

Characteristics

Chromosome territories are spheroid with diameters on the order of one to few micrometers. Nuclear compartments devoid of DNA called interchromatin compartments have been reported to tunnel into chromosome territories to facilitate molecular diffusion into the otherwise tightly packed chromosome-occupied regions.

History and experimental support

The concept of chromosome territories was proposed by Carl Rabl in 1885 based on studies of Salamandra maculata. Chromosome territories have gained recognition using fluorescence labeling techniques ( fluorescence in situ hybridization). Studies of genomic proximity using techniques like

chromosome conformation capture Chromosome conformation capture techniques (often abbreviated to 3C technologies or 3C-based methods) are a set of molecular biology methods used to analyze the spatial organization of chromatin in a cell. These methods quantify the number of int ...

have supported the chromosome territory concept by showing that DNA-DNA contacts predominantly happen within particular chromosomes.

References

{{reflist Molecular biology Nuclear organization

Characteristics

History and experimental support

See also

References