|MadSci Network: Cell Biology|
Hi Mark, Neurons are somatic cells, and therefore contain the same genetic information as other somatic cells (in contrast to germ cells such as sperm and eggs, that contain half as many chromosomes as somatic cells). All somatic cells in an organism have the same DNA, collectively called the genome. A gene is “transcribed” into messenger RNA, which is then “translated” into a protein. Kinases are enzymes (proteins that catalyze biochemical reactions in the cell) that add a phosphate group to other proteins. Conversely, phosphatases are enzymes that remove phosphate groups from other proteins. Proteins, and interactions between proteins, can be activated or inhibited by the addition or removal of phosphate groups, and this can influence cell behavior. To answer your 2nd question, kinases can impact transcription of genes, which dictates which proteins are expressed in the cell, but kinases cannot change the genetic information in a cell. Regardless, kinases are key proteins in cell signaling. Signal transduction allows a cell to respond to extracellular or intracellular cues, resulting in a variety of cell behaviors including cell migration, proliferation, cell survival, etc. For example, kinases are involved in "firing" at a neuronal synapse. Release of neurotransmitters and ions into the space between nerve cells (called the synaptic cleft) involves kinases, as does uptake of the neurotransmitters by the neighboring cell. (Keep in mind that many proteins besides kinases are involved in this process.) If this sounds complicated, it’s because it is complicated. There are many levels of regulation in cells, but somehow it all works! Please write back if you have any more questions, or want more specific information. Sarah Earley Postdoctoral Fellow Albany Medical College
Try the links in the MadSci Library for more information on Cell Biology.