Cajal body

Revision as of 01:39, 18 October 2007 by Jackbot (talk | contribs) (Robot: Automated text replacement (-(?ms)^(.*)$ +\1 {{WikiDoc Help Menu}}))
Jump to: navigation, search

Cajal bodies (CBs) are spherical sub-organelles found in the nucleus of proliferative cells like tumor cells, or metabolically active cells like neurons. They were first reported by Santiago Ramón y Cajal in 1903, who called them nucleolar accessory bodies due to their association "with the nucleoli in neuronal cells."[1] Electron microscopists gave them the name "coiled body" because of their shape in EM sections. More recently, in honor of Ramón, they were termed Cajal bodies (CBs).[1]

They are about 0.1 - 2.0 micrometres and are found one to five per nucleus; the number varies over the cell cycle and in different types of cells. Cajal bodies are possibly sites of assembly or modification of the transcription machinery of the nucleus.[2]

Cajal bodies are only found in nuclei of plant, yeast, and animal cells. The cells are usually demonstrating high levels of transcriptional activity, including cells that are rapidly dividing.[1]

CBs are bound to the nucleolus by coilin proteins.

References

  1. 1.0 1.1 1.2 Ogg S, Lamond A (2002). "Cajal bodies and coilin--moving towards function". J Cell Biol. 159 (1): 17–21. PMID 12379800.
  2. Cremer T, Cremer C (2001). "Chromosome territories, nuclear architecture and gene regulation in mammalian cells". Nat Rev Genet. 2 (4): 292–301. PMID 11283701.

Linked-in.jpg