Regulation of Erythroid Gene Expression by the Transcription Factor EKLF
Year: 2004
Type: dissertation
Abstract: The human body consists of a huge number of cells. At the base of all these cells is one \nfertilized oocyte. By cell divisions the number of cells is increased during development, \nand cells specialize into various types of cells, i.e. muscle, brain and blood cells. Groups of \nspecialized cells form the various tissues. DNA contains the blueprint of all cells. By each \ncell division the DNA is duplicated and equally distributed over the two daughter cells. \nHence, practically all the cells contain identical genetic information. The DNA in each cell \ncontains about 25.000 genes. Each gene contains information necessary to produce a particular \nprotein. These proteins are involved in many processes such as energy metabolism, \ncell composition and gene regulation.\n\nAlthough all cells contain the same genetic information, they specialize into various cell \ntypes. For this, the genes are specifically activated or repressed. A tight regulation of the \ngenes makes it possible to specialize into a particular type of cell. Transcription factors play \nan important role in this tight regulation of activating or repressing genes. EKLF is such a \ntranscription factor. EKLF is mainly expressed in red blood cells. These cells give blood \nits red color. They carry oxygen from lungs to tissues in the body that require the oxygen \nfor energy metabolism. Red blood cells are filled with hemoglobin that actually binds the \noxygen. Each hemoglobin particle consists of two a-globin, two ß-globin and four heme \nmolecules. The genetic blueprint for the ß-globin gene is called the ß-globin locus. In the \nmouse, this locus contains four globin genes. Two of them, the embryonic ß-globin genes, \nare active during embryonic development of the mice and the other two, the adult ß-globin \ngenes are activated later in development and stay active during the rest of the lifespan of the \nmouse. Apart from the four ß-globin genes, the locus contains regulatory elements. These \ninclude the Locus Control Region (LCR), and a number of other hypersensitive sites. The \nLCR is required for a proper regulation of the globin genes; in absence of the LCR the genes \nare not activated, and mutations in the LCR can lead to impaired activation. The LCR is \nlocated relatively far from the genes it controls. However, when a globin gene is active in \nred blood cells, the LCR is physically in close proximity to this gene. In fact, the globi
Author: Roy Drissen
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W1539337945