are located within one square mile of each other in midtown Manhattan.

The New York City life sciences got a boost this year when two biotechs, ImClone Systems Inc. and Eyetech Pharmaceuticals Inc., announced plans to expand operations in the city.

DELIVERY METHODS:© 2003, Elsevier ScienceSmall interfering RNAs (siRNAs) may be synthesized and then transfected into cells (A), or generated by the RNAase activity of Dicer (B) on short hairpin RNAs (shRNAs) transcribed in vivo (C). Transfection (D) and integration (E) of plasmid DNA containing a selectable marker and a promoter to drive shRNA expression are used to generate a stable cell line. Alternatively, DNA encoding shRNA may be introduced by viral-mediated transduction (D). siRNAs (

SHAPING A COMMITMENT:© 2004 Cell PressBrightfield images of hMSCs plated onto small 1,024 μm2 or large 10,000 μm2 fibronectin islands after 1 week in growth or mixed media. Lipids stain red, alkaline phosphatase stains blue. Scale bar = 50 μm. (From R. McBeath et al., Dev Cell, 6:483–95, 2004)Researchers have tried for years to make stem cells differentiate into specific cell types. This work usually involves bathing the cells in molecular signals that affect their fate

papers find mechanism at work at transcriptional level in human cells

Courtesy of Brian OakleyResearchers say they have identified bacteria thriving at the lowest temperatures for which such activity is documented. Several such ultracold microbe findings are making the possibility of life elsewhere in the Solar System seem less distant and are presenting new biotechnological possibilities.The University of Washington's James Staley and colleagues say they cultured rod-shaped bacteria, tentatively named Psychromonas ingrahamii, from off Alaska's coast, at -12°

Courtesy of Cesare BrizioResearchers say they have safely delivered therapeutic agents into mammalian cells by attaching them to insect-derived peptides. The technique may help overcome the difficulties in getting vaccines and drugs into cells where they're needed. The Wistar Institute's Laszlo Otvos, Jr., and colleagues found that pyrrhocoricin, an antimicrobial peptide originally isolated from the European sap-sucking insect, Pyrrhocoris apterus, entered the cells without damaging them.An arti

STRANDED SEX:© 2003 Elsevier ScienceIn this two-pot recombination scheme a ribozyme is incubated with an excess of RNA substrate A-B. The 3' portion of the substrate is covalently attached to the 3' end of the ribozyme in a "pick-up-the-tail" (PUTT) reaction. When the ribozyme is purified and incubated with an excess of substrate C-D, recombination (REC) of the substrates results in the product C-B. Exogenous GTP marginally improves recombination frequency which ranges from 5% to 45%. (From

In a study that could offer a glimpse into sleep's still poorly understood functions, researchers have identified genes upregulated specifically during sleep.1 The findings contain surprises, investigators say. One is simply that there are many such genes, at least as many as are turned on while awake, belying the common-sense view that sleep implies inactivity. Another is that the sleep-related changes in gene expression extend to the cerebellum, a structure not previously known to participate

Indifferent to textbook dogma, some researchers have long suspected that bacteria really do have sex. They merge their genomes, research suggests, possibly by whole-cell fusion. Investigators liken the phenomenon to egg fertilization and distinguish it from conjugation, in which bacteria pass along bits of genetic material. A decade ago, Jean-Pierre Gratia, now at the Pasteur Institute of Brussels, Belgium, reported that mixing two nonconjugating Escherichia coli strains produced cells with both

Courtesy of Preston Huey, © 2003 AAAS  LIFE IN THE HOT SEAT: In one hypothetical model, an alkaline hydrothermal solution of constant temperature and pH may have convectively pumped through a confining porous mound of precipitated clays, hydroxides such as Mg(OH)2, and iron nickel sulfides into a cool and acidulous ocean. In 1953 a University of Chicago graduate student, Stanley Miller, shot electric sparks into an apparatus that circulated water, methane, ammonia, and hydrogen in a

David Ho discusses promising vaccine approaches, improved therapies, and remaining obstacles