Genomics
The term "genomics" refers to the sequencing and functional analysis of the complete genome of an organism. A "genome" is the entire set of "genes" that a cell contains. A "gene" is a unit of DNA that codes for a specific molecule of RNA (Ribonucleic acid). This RNA molecule is "translated" into a specific protein that again has a specific function in a cell. In 2003, the "Human Genome Project" published the complete sequence of the human genome after 13 years of intensive research. The same task was also done for the mouse genome. The sequencing data refer to "structural genomics", whereas the specific function of a gene is identified by means of "functional genomics":
In a multicellular mammalian organism with its vast number of 10 trillion cells (10.000.000.000.000), every single cell still possesses approximately 40.000 genes, although usually only a small fraction of them is active. Just as fascinating, every single cell has all the genes and the (theoretical) capacity to develop into any specialised type of cell in the body. For a mammal this means more than 200 different tissues. This phenomenon is what we call "pluripotency". Two general principles have a diametric character: proliferation and differentiation, self-renewal and specialization. The faster cells renew themselves, the less they differentiate. The more cells are specialisation, the less they have the capacity to renew. These phenomena are regulated by interaction between genes and transcription factors.
Gene Regulation
Every mammalian cell contains approximately 40.000 genes. All processes of an embryonic stem cell, such as nutrition, movement, defence or self-renewal are regulated by interactions between genes and a variety of "transcription factors". Some genes are permanently expressed in all embryonic stem cells. These so-called "housekeeping genes" are responsible for vital metabolic functions (for example respiration) necessary for all cells. Different genes are expressed when an embryonic stem cell enters a particular pathway of its differentiation, for example to become a multipotent bone marrow stem cell. Other genes are permanently expressed only in those cells that have already differentiated in a particular way. For example, a beta-cell of the islet of Langerhans in the pancreas continuously expresses the genes required for the production of insulin. Other genes are expressed only when some conditions change in the surrounding of the cell.
Embryonic stem cells use several methods to control their gene function. The most important and widely-used mechanism is to control the rate of transcription of the gene. The genes, the signals and the regulation of both processes are the main fields of interest in the FunGenES consortium. The sequence of this interaction is one key to understanding development. Certain signals "activate" genes which "push" the undifferentiated cells in such a way as to become for instance multipotent bone-marrow stem cells or, after even more signalling-cascades, to become terminally differentiated like specialised cardiomyocytes in the heart.
Functional Genomics
Functional genomics refers to the analysis of gene functions by means of "high throughput" methods in combination with data processing on a large scale. Functional genomics extends the possibilities of biological investigations from studying only single genes to studying all genes of a cell at once in a systematic manner.
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