For Genes Author: Holly Ahern For a geneticist, pinpointing a mutation in a human gene that might be responsible for an inherited disease can be likened to the proverbial search for a needle in a haystack. While mo-lecular biologists sift through the 3 billion base pairs in the human genome in search of disease-causing genes, other scientists choose to approach the problem from the perspective of the mouse, a model system for mammal research. Because mice and humans are members of the same gr

Biological Research Author: Holly Ahern It's the type of problem that crops up in cell biology, molecular biology, and neuroscience laboratories constantly. Hidden amid a compendium of compounds in a crude cell extract is a protein that researchers have sought since its gene was cloned months before. Perhaps the protein is an enzyme for which the catalytic mechanism has not yet been determined. Or maybe the compound is a recombinant protein that shows promise as a pharmaceutical agent. In eith

Ways Author: Holly Ahern In many areas of neurobiology and cell biology, researchers who a decade ago were confined to studying stained tissues are today using their microscopes in new ways to directly observe dynamic events as they occur in living cells. Although the optical systems of microscopes have not changed dramatically over the last quarter of a century, new methods of acquiring images and processing microscopic infor-mation have indelibly changed the way that scientists view the mic

Genome Author: Holly Ahern SIDEBAR: Selected Suppliers of DNA Sequencing Equipment and Supplies Since the Human Genome Project (HGP) was launched five years ago, human geneticists working to decipher the code of nucleotides in the DNA of human cells have enthralled the public with discoveries of numerous genes that are responsible for human diseases, such as cancer-related genes. Different groups of scientists in laboratories all over the world are participating in this project, taking apart t

SIDEBAR: Selected Suppliers of Immunoassays and Assay Systems Immunoassays combine principles of immunology and chemistry into tests that are used by scientists in practically every discipline, including fields as diverse as molecular biology and environmental science. In research applications, immunoassays such as immunoblotting (detecting membrane-bound proteins), immunohistochemistry (cell or tissue staining), and enzyme immunoassays provide a sensitive and specific means of detecting targe

if (n == null) The Scientist - The Immune Response The Scientist 9[18]:18, Sep. 18, 1995 Tools The Immune Response By Holly Ahern Imagine that you've just cloned a gene for a bacterial enzyme with unique structural properties and you want to find out more about it. What natural role does the enzyme play, you wonder, and do organisms other than bacteria produce it? To answer these questions, you could screen countless genomic libraries for clones bearing si

For researchers who made solutions a quarter-century ago, filtration involved deftly folding a round piece of filter paper into a triangular shape so that it would fit inside the inverted cone of a funnel. Once the paper was fitted inside the funnel, they could filter practically any solution, even those thick with solute--providing they had hours of time to spend watching the clear liquid drip into a flask as the particulate material in the funnel grew thicker and thicker. If they were in a r

Investment Author:Holly Ahern If you were to ask several life scientists to name a particular biochemical product that they simply could not do without, you'd probably get a myriad of answers that would mirror the research interests of the group you questioned. A molecular evolutionist trying to differentiate two closely related species of monkeys by restriction fragment-length polymorphism (RFLP) analysis might cite restriction enzymes, which can cut DNA into pieces of varying length. A cell b

The Scientist 9[14]:, Jul. 10, 1995 News The Rodent Revolution By Holly Ahern A nude mouse What do nudes, knockouts, and gnotobiotics have in common? Contrary to the images these terms might conjure up, they are not characters in an X-rated horror film set on an alien planet. These are all laboratory animals created expressly for use by scientists in several areas of biology and biomedical research. The applications for laboratory animals are many and varied, including

What would you do if your research interests revolved around obtaining DNA from a bacterium preserved for millions of years in the gut of a bee stuck in amber, matching up a murderer to crime- scene blood half a century old, or cloning genes from a 1,000- year-old mummy? Most scientists would first consider PCR--the polymerase chain reaction--as a technique for approaching problems such as these. With PCR, minute quantities of nucleic acids can be amplified millions of times into sufficient qua

WIZARD SERIES: Promega Corp. offers a variety of DNA purification products. One of the first steps that biologists perform in the quest to identify a gene, learn the function of a particular protein, or identify the perpetrator of a violent crime is to purify the genetic material away from other cellular constituents. Where once purifications were nearly as complicated as the biophysical assays performed on the products, now they are in many cases the simplest part of the experiment. While man

Imagine an orchestra composed of 100 musicians, all playing a different instrument. Now consider what you'd hear if all of the musicians began playing a symphony, but with each starting on a different note, or playing in a different key. If the individual members of the orchestra didn't communicate, their performance would probably sound like a cacophony of screeching tires and wailing animals--certainly not something you'd want to pay money to hear! Add a conductor with sheet music, and the ou