By engineering cells to express a modified RNA called "Spinach, " researchers have imaged small-molecule metabolites in living cells and observed how their levels change over time. Metabolites are the products of individual cell metabolism. The ability to measure their rate of production could be used to recognize a cell gone metabolically awry, as in cancer, or identify the drug that can restore the cell's metabolites to normal. Researchers at Weill Cornell Medical College say the advance, described in Science, has the potential to revolutionize the understanding of the metabolome, the thousands of metabolites that provide chemical fingerprints of dynamic activity within cells. "The ability to see metabolites in action will offer us new and powerful clues into how they are altered in disease and help us find treatments that can restore their levels to normal, " says Dr.
Researchers at the Kimmel Cancer Center at Jefferson have demonstrated for the first time that the metabolic biomarker MCT4 directly links clinical outcomes with a new model of tumor metabolism that has patients "feeding" their cancer cells. Their findings were published online March 15 in Cell Cycle. To validate the prognostic value of the biomarker, a research team led by Agnieszka K. Witkiewicz, M.D., Associate Professor of Pathology, Anatomy and Cell Biology at Thomas Jefferson University, and Michael P. Lisanti, M.D., Ph.D., Professor and Chair of Stem Cell Biology and Regenerative Medicine at Jefferson, analyzed samples of patients with triple negative breast cancer, one of the most deadly of breast cancers, with fast-growing tumors that often affect younger women. A retrospective analysis of over 180 women revealed that high levels of the biomarker MCT4, or monocarboxylate transporter 4, were strictly correlated with a loss of caveolin-1 (Cav-1), a known marker of early tumor recurrence and metastasis in several cancers, including prostate and breast.
In the beginning - of the ribosome, the cell's protein-building workbench - there were ribonucleic acids, the molecules we call RNA that today perform a host of vital functions in cells. And according to a new analysis, even before the ribosome's many working parts were recruited for protein synthesis, proteins also were on the scene and interacting with RNA. This finding challenges a long-held hypothesis about the early evolution of life. The study appears in the journal PLoS ONE. The "RNA world" hypothesis, first promoted in 1986 in a paper in the journal Nature and defended and elaborated on for more than 25 years, posits that the first stages of molecular evolution involved RNA and not proteins, and that proteins (and DNA) emerged later, said University of Illinois crop sciences and Institute for Genomic Biology professor Gustavo Caetano-AnollĂ s, who led the new study.
The winter sun feels welcome, but not so a summer sunburn. Research over the past 20 years has shown that proteins on the surface of nerve cells enable the body to sense several different temperatures. Now scientists have discovered how just a few of these proteins, called ion channels, distinguish perhaps dozens of discrete temperatures, from mildly warm to very hot. Researchers showed that the building blocks, or subunits, of heat-sensitive ion channels can assemble in many different combinations, yielding new types of channels, each capable of detecting a different temperature. The discovery, in cell cultures, demonstrates for the first time that only four genes, each encoding one subunit type, can generate dozens of different heat-sensitive channels. "Researchers in the past have assumed that because there are only four genes, there are only four heat-sensitive channels, but now we have shown that there are many more, " said Jie Zheng, leader of the research and an associate professor of physiology and membrane biology at the UC Davis School of Medicine.
A new study, published in the March 9 issue of Science, reveals that by engineering cells to express a modified RNA called "Spinach", researchers from the Weill Cornell Medical College have advanced in reproducing small-molecule metabolites, i.e. intermediates and products of individual cell metabolism in living cells and observed that metabolite levels changed with time. The discovery of measuring a metabolite's production rate is likely to transform scientists' understanding of the metabolome and could prove beneficial in identifying whether a cell is metabolically dysfunctional like in cancer, or to help develop drugs that can restore a normal function in metabolites. A metabolome consists of thousands of metabolites that provide chemical fingerprints of dynamic activity within cells.