Chromosome territories

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

Interphase chromosomes are long DNA strands that are extensively folded, and are often described as appearing like a bowl of spaghetti. 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 S. cerevisiae is an exception to this.

Characteristics

Chromosome territories are spheroid with a diameters on the order of a 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 Rabĺs in 1885 based on studies of bacteria.

Chromosome territories have gained recognition only as fluorescence labeling techniques like fluorescence in situ hybridization have gained widespread use.

Studies of genomic proximity using techniques like chromosome conformation capture have supported the chromosome territory concept by showing that DNA-DNA contacts predominantly happen within particular chromosomes.