News tagged with cell nucleus

Related topics: genes , cancer cells , protein , gene expression , genetic material

Discovery reveals chromosomes organize into 'yarns'

Chromosomes, the molecular basis of genetic heredity, remain enigmatic 130 years after their discovery in 1882 by Walther Flemming. New research published online in Nature by the team of Edith Heard, PhD, from the Curie ...

Apr 11, 2012
popularity 4.7 / 5 (3) | comments 0 | with audio podcast

Researchers engineer blood stem cells to fight melanoma

Researchers from UCLA's cancer and stem cell centers have demonstrated for the first time that blood stem cells can be engineered to create cancer-killing T-cells that seek out and attack a human melanoma. The researchers ...

Nov 28, 2011
popularity 5 / 5 (4) | comments 1 | with audio podcast

Biochemical mechanisms of memory

A discovery by a research team led by Ryohei Yasuda at the Max Planck Florida Institute for Neuroscience has significantly advanced basic understanding of biochemical mechanisms associated with how memories are formed.

Dec 09, 2013
popularity 4.7 / 5 (6) | comments 1 | with audio podcast

Anti-ageing hormone receptors

(Medical Xpress)—A reduced caloric intake increases life expectancy in many species. But how diet prolongs the lives of model organisms such as fruit flies and roundworms has remained a mystery until recently.

Aug 07, 2013
popularity 4.8 / 5 (5) | comments 0 | with audio podcast

Cell nucleus

In cell biology, the nucleus (pl. nuclei; from Latin nucleus or nuculeus, or kernel), also sometimes referred to as the "control center", is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression--the nucleus is therefore the control center of the cell.

The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and separates its contents from the cellular cytoplasm, and the nuclear lamina, a meshwork within the nucleus that adds mechanical support, much like the cytoskeleton supports the cell as a whole. Because the nuclear membrane is impermeable to most molecules, nuclear pores are required to allow movement of molecules across the envelope. These pores cross both of the membranes, providing a channel that allows free movement of small molecules and ions. The movement of larger molecules such as proteins is carefully controlled, and requires active transport regulated by carrier proteins. Nuclear transport is crucial to cell function, as movement through the pores is required for both gene expression and chromosomal maintenance.

Although the interior of the nucleus does not contain any membrane-bound subcompartments, its contents are not uniform, and a number of subnuclear bodies exist, made up of unique proteins, RNA molecules, and particular parts of the chromosomes. The best known of these is the nucleolus, which is mainly involved in the assembly of ribosomes. After being produced in the nucleolus, ribosomes are exported to the cytoplasm where they translate mRNA.

This text uses material from Wikipedia licensed under CC BY-SA