A Planet of Viruses by
Viruses are the smallest living things known to science, yet they hold the entire planet in their sway. We are most familiar with the viruses that give us colds or the flu, but viruses also cause a vast range of other diseases, including one disorder that makes people sprout branch-like growths as if they were trees. Viruses have been a part of our lives for so long, in fact, that we are actually part virus: the human genome contains more DNA from viruses than our own genes. Meanwhile, scientists are discovering viruses everywhere they look: in the soil, in the ocean, even in caves miles underground. This fascinating book explores the hidden world of viruses--a world that we all inhabit. Here Carl Zimmer, popular science writer and author of Discover magazine's award-winning blog The Loom, presents the latest research on how viruses hold sway over our lives and our biosphere, how viruses helped give rise to the first life-forms, how viruses are producing new diseases, how we can harness viruses for our own ends, and how viruses will continue to control our fate for years to come. In this eye-opening tour of the frontiers of biology, where scientists are expanding our understanding of life as we know it, we learn that some treatments for the common cold do more harm than good; that the world's oceans are home to an astonishing number of viruses; and that the evolution of HIV is now in overdrive, spawning more mutated strains than we care to imagine. The New York Times Book Review calls Carl Zimmer "as fine a science essayist as we have." A Planet of Viruses is sure to please his many fans and further enhance his reputation as one of America's most respected and admired science journalists.
RNA by
In RNA: Life's Indispensable Molecule, Jim Darnell provides a comprehensive and captivating account of RNA research, illuminated by his own life-long and celebrated engagement in the field. Darnell describes how scientists unraveled fundamental questions about the biochemical and genetic importance of RNA--how mRNAs are generated and used to produce proteins, how noncoding and catalytic RNAs mediate key cellular processes, and how RNA molecules likely initiated life on Earth. With a scope extending from the early 20th century to the present day, and with the clarity expected from an accomplished textbook author, he conveys the intellectual context in which these questions first arose and explains how the key experiments were structured and answers obtained. The book is geared towards scientists from the graduate level on up, and will particularly appeal to active investigators in RNA biology, educators of molecular biology and biochemistry, and science historians.
RNAi by
Martin Latterich covers the basic concepts and mechanisms of RNAi, transfection of cells with siRNAs, the design and validation of reagents, techniques in different organisms, large-scale RNAi screening, applications in drug discovery, and potential uses as a therapeutic agent.
DNA contains the instructions for making all the proteins in the body (roughly 25,000 in humans). Each gene carries instructions for one protein. To produce a protein, the cell goes through 2 steps :
Transcription : the code on the DNA is copied to mRNA. The 2006 Nobel prize for Chemistry was given to Roger Kornberg who worked out the details of transcription.
Translation : the mRNA code is read by ribosomes in the cytoplasm, which join amino acids together.
The code on DNA and mRNA is a triplet code : 3 bases code for 1 amino acid eg GGA codes for Glycine.
One code on mRNA is the "start" code : AUG. Several codes on mRNA signal "stop" eg UGA.
Transfer RNAs ( tRNA) bring each amino acid to the ribosome. Each tRNA has an anticodon which matches the 3 base codon on mRNA. The ribosome moves along the mRNA strand, adding amino acids one at a time.
Small pieces of "interfering RNA" could be used medically to switch off particular genes, for example to cure cancer or genetic diseases. Gene-blocking therapy. The 2006 Nobel Prize for Medicine was awarded to the two scientists who discovered RNA interference.
In eukaryotic cells, genes have introns ( that do not code for proteins "junk DNA" ) and exons ( that code for proteins ). Some of the introns probably have some function (so they are not really "junk"): "Junk DNA"
Mutations (changes in the DNA code ) can cause a different protein to be made. Fig 13-20. Most mutations are harmful eg cancer, but very occasionally they produce a better protein than the original, which is important in evolution.
Last edited April 2015 by David Byres, David.Byres@fscj.edu