MADLANSA%FORDMULC.BITNET@mvs.oac.ucla.edu (05/23/91)
Can someone give a layman explanation of what nucleoside analog mean? thanks.
rpetsche@mrg.PHYS.CWRU.Edu (rolfe g petschek) (05/24/91)
In article <1991May23.135727.5972@cs.ucla.edu> MADLANSA%FORDMULC.BITNET@mvs.oac.ucla.edu writes: >Can someone give a layman explanation of what nucleoside analog mean? > >thanks. As you may know the genetic material HIV is, during various stages of its life cycle RNA and DNA which are in essence double strands of particular molecules tied one to the other. The virus (and all known living beings) reproduce in part by making new strands of these molecules. This is done by unwinding the helix of the double strand and adding molecules one after the other on either side complimenting the molecules on the other side of the strand. Consider molecules which are enough alike the appropriate molecules so that the ensymes which perform this process can not tell the difference between them and the correct molecules when they are being added to the chain but which are very different in some way. Then this process can be disrupted. For example a molecule could be such that it has the part which allows it to stick to the part of the chain strand to which molecules are added but does not have that part of the molecule which will allow the next molecule to stick to it. Such molecules exist, ddI is an example. Then if these molecules are used to try to reproduce DNA or RNA they will stop this reproduction, disrupting and eventually killing the organism which is trying to reproduce. Thus they kill 'growing' things - and are used for treatment of serious viral infections and cancer, both of which are growing very quickly. The draw back, of course, is that such molecules will also generally make it very hard on the organism in which they are as they will also disrupt the ordinary growth and replacement of cells - hence the very serious side effects of these drugs. Hence also the relatively quick appearance of drugs for HIV - AZT was actually first synthesized as an anti-cancer drug. -- Rolfe G. Petschek Petschek@cwru.bitnet Associate Professor of Physics rgp@po.cwru.edu Case Western Reserve University (216)368-4035 Cleveland Oh 44106-7970