Image: Ned Shaw The cell--the irreducible unit of life on Earth--has an estimated history nigh on 3.5 billion years. Scientists since Charles Darwin have attempted to trace that history to a so-called last common ancestor. Comparative physiology and fossil records can take one only so far, so many researchers are trying to reach the tree of life's roots with tools of a genetic nature. Yet, the more they dig, the more convoluted those roots appear to be. Lateral gene transfer, the square peg in

Photos: Ian Parker & Mark Miller SHALL WE DANCE? Key immune players cut a rug in a lymph node. Shown are T cells (green), B cells (red), and dendritic cells (blue). Inset: T cells and reticular fibers (red). Both pictures were acquired using TPLSM. Using a technique called two-photon laser- scanning microscopy (TPLSM) researchers can visualize, in three dimensions, the cellular waltzes by which the mammalian immune system develops and reacts to infection. The technique enables two low-en

Photo: Courtesy of the Wistar Institute What takes a man from checking midnight inventories at grocery stores in Ohio to directing one of the oldest private biomedical research institutes in the United States? Says the man who did it: strong values, great mentors, and a penchant for late nights. "All you have to do is look at a person's bookshelf and you'll see what they value," explains Russel E. Kaufman, the recently appointed director and CEO of Philadelphia's Wistar Institute. In taking c

Image: Courtesy of David J. Mangelsdorf YIN AND YANG: Although they play opposite roles in bile acid production, these RXR heterodimers synergistically modulate cholesterol absorption and transport. When the molecular basis of Tangier disease was discovered in 1999,1 researchers lined up to study this orphan genetic disorder. Patients with Tangier have a propensity for heart disease and atherosclerosis, making this rare malady a model for some pressing health problems found in industrial

The Faculty of 1000 is aWeb-based literature awareness tool published by BioMed Central. For more information visit www.facultyof1000.com. Cells control their responses to the presence or absence of oxygen by an elegant system of checks and balances. Recent structural studies clarify some high-impact findings in hypoxia research, lending insight into the dynamic nature of HIF-1a , the hypoxia-induced transcription factor. This infamous molecule, when unchecked, turns on genes that enhance tumo

Methanogenic anaerobe yields pyrrolysine, the first new genetically encoded residue since 1986.

A group of speakers selected to embody the past, present, and future of plant science portrayed life's diversity as being in a precarious situation. Half the species on the planet could be wiped out by the end of the century, some say. "We are playing the endgame," said Edward O. Wilson, Pellegrino University professor and curator of entomology at the Museum of Comparative Zoology, Harvard University. The inauguration of a multimillion-dollar plant science center at the New York Botanical Garden

For a team at the University of California, San Diego, nine years of tinkering with arsenic paid off in the development of a new technique that can tag proteins with different colors over time and even zero in to electron microscopic resolution. Roger Tsien, Howard Hughes Medical Institute investigator and professor of pharmacology, chemistry, and biochemistry at UCSD, says the project started with the suggestion from a colleague that one can tag a two-cysteine sequence in a protein with a singl

Imbedded in the genomes of creatures as varied as mouse and man are retroviral remnants. These artifacts of ancient infections result from RNA viruses inserting DNA copies of themselves into their hosts' genomes. Sometimes they hit the jackpot and make their way into the germ line. Sorted and shuffled over the eons, some of these ancient endogenous viruses have serendipitously developed the ability to shield cells against new viruses. Research on retroviruses and resistance to them in mice and o

Data derived from the Science Watch/Hot Papers database and the Web of Science (ISI, Philadelphia) show that Hot Papers are cited 50 to 100 times more often than the average paper of the same type and age. Courtesy of Peter UetzPeter Uetz As a graduate student, Peter Uetz investigated embryonic development in mice and chickens, working to explain how deformity relates to the protein formin. Uetz, then working at the European Molecular Biology Laboratory in Heidelberg, Germany, found few answers

If mapping the entire human proteome isn't challenge enough, consider this: The Human Proteome Organization, created this past year, aims to coordinate the efforts of the many public and private groups moving into the proteomic field.1 HUPO president Samir Hanash hopes an April 29 meeting at the National Institutes of Health will solidify plans and collaborations to characterize all blood serum proteins, create a library of antibodies to every human protein, and put the data collected in a user

Smoldering differences between the Celera Genomics Group and the Human Genome Project erupted last month as three leaders of the international public consortium published an online article in the Proceedings of the National Academy of Sciences (PNAS)1 criticizing the results published last year by Celera.2 For the first time in scientific literature, Robert Waterston of Washington University, Eric Lander of the Whitehead Institute for Biomedical Research's Center for Genome Research, and John Su