Submitted by ksvitil on Wed, 2010-08-04 17:00
One key to fighting diseases such as leukemia and anemia is gaining an understanding of the genes and molecules that control the function of hematopoietic—or blood—stem cells, which provide the body with a constant supply of red and white blood cells and platelets. Biologists at Caltech have taken a large step toward that end, with the discovery of a novel group of molecules that are found in high concentrations within hematopoietic stem cells and appear to regulate their production.
Submitted by ksvitil on Mon, 2010-08-02 23:00
Our belief as to whether we will likely succeed or fail at a given task—and the consequences of winning or losing—directly affects the levels of neural effort put forth in movement-planning circuits in the human cortex, according to a new brain-imaging study by Caltech neuroscientists.
Submitted by ksvitil on Mon, 2010-07-19 11:00
Biologists at Caltech have demonstrated a connection between multiple sclerosis (MS)—an autoimmune disorder that affects the brain and spinal cord—and gut bacteria.
Submitted by ksvitil on Fri, 2010-07-02 02:00
When does a cell decide its particular identity? According to Caltech biologists, in the case of T cells—immune system cells that help destroy invading pathogens—the answer is when the cells begin expressing a particular gene called Bcl11b.
Submitted by lorio on Wed, 2010-06-30 07:00
How a pregnant body tolerates a fetus that is biologically distinct from its mother has long been a mystery. Now, a pair of scientists from Caltech have shown that females actively produce a particular type of immune cell in response to specific fetal antigens—immune-stimulating proteins—and that this response allows pregnancy to continue without the fetus being rejected by the mother's body.
Submitted by ksvitil on Thu, 2010-06-03 18:00
Biologists at Caltech have pinpointed molecular changes that helped allow the global spread of resistance to the antiviral medication Tamiflu (oseltamivir) among strains of the seasonal H1N1 flu virus.
Submitted by ksvitil on Thu, 2010-05-20 16:00
Biologists from Caltech and Yale University have identified two genes, the leucokinin neuropeptide and the leucokinin receptor, that appear to regulate meal sizes and frequency in fruit flies. Both genes have mammalian counterparts that seem to play a similar role in food intake, indicating that the steps that control meal size and meal frequency are not just behaviorally similar but are controlled by the same genes throughout the animal kingdom.
Submitted by lorio on Mon, 2010-05-17 07:00
The sepals of the plant Arabidopsis thaliana—commonly known as the mouse-eared cress—are characterized by an outer layer of cells that vary widely in their sizes, and are distributed in equally varied patterns and proportions. Scientists have long wondered how the plant regulates cell division to create these patterns. Melding time-lapse imaging and computer modeling, a team of scientists led by biologists from Caltech has provided a somewhat unexpected answer to this question.
Submitted by lorio on Wed, 2010-04-14 07:00
A typical human cell contains hundreds of mitochondria—energy-producing organelles—that continually fuse and divide. Relatively little is known, however, about why mitochondria undergo this behavior. Now, scientists at the Caltech have taken steps toward a fuller understanding of this process by revealing just what happens to the organelle, its DNA (mtDNA), and its energy-producing ability when mitochondrial fusion fails.
Submitted by lorio on Fri, 2010-04-02 07:00
Scientists from the Caltech have provided the first-ever glimpse of the structure of a key protein—gp120—found on the surface of a specific subgroup of the human immunodeficiency virus, HIV-1. In addition, they demonstrated that a particular antibody to gp120 makes contact not only with the protein, but with the CD4 receptor that gp120 uses to gain entrance into the body's T cells.