Biology News Net - Molecular & Cell Biology

Just like old times: Generating RNA molecules in water

Fri, 20 Nov 2009 15:12:26 -0500

A key question in the origin of biological molecules like RNA and DNA is how they first came together billions of years ago from simple precursors. Now, in a study appearing in this week's JBC, researchers in Italy have reconstructed one of the earliest evolutionary steps yet: generating long chains of RNA from individual subunits using nothing but warm water.

Pushing the brain to find new pathways

Tue, 17 Nov 2009 16:29:07 -0500

Until recently, scientists believed that, following a stroke, a patient had about six months to regain any lost function. After that, patients would be forced to compensate for the lost function by focusing on their remaining abilities. Although this belief has been refuted, a University of Missouri occupational therapy professor believes that the current health system is still not giving patients enough time to recover and underestimating what the human brain can do given the right conditions.

How cells tolerate DNA damage -- start signal for cell survival program identified

Mon, 16 Nov 2009 17:19:50 -0500

Cancer researchers of the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch have gained new insights into how cells react to DNA damage. Dr. Michael Stilmann, Dr. Michael Hinz and Professor Claus Scheidereit have shown that the protein PARP-1, which detects DNA damage within seconds, activates the transcription factor NF-kappaB, a well-known regulator of gene expression. NF-kappaB triggers a survival program, which blocks programmed cell death. The activation of NF-kappaB is thought to be one of the potential causes for tumor cell resistance to chemo and radiation therapy. (Molecular Cell, online, doi 10.1016/j.molcel.2009.09.032; Preview: doi 10.1016/j.molcel.2009.10.022)*.

Chromosomes dance and pair up on the nuclear membrane

Fri, 13 Nov 2009 22:15:09 -0500

Meiosis – the pairing and recombination of chromosomes, followed by segregation of half to each egg or sperm cell – is a major crossroads in all organisms reproducing sexually. Yet, how the cell precisely choreographs these chromosomal interactions is a long-standing question.

To make memories, new neurons must erase older ones

Thu, 12 Nov 2009 20:33:09 -0500

Short-term memory may depend in a surprising way on the ability of newly formed neurons to erase older connections. That's the conclusion of a report in the November 13th issue of the journal Cell, a Cell Press publication, that provides some of the first evidence in mice and rats that new neurons sprouted in the hippocampus cause the decay of short-term fear memories in that brain region, without an overall memory loss.

Vibrations key to efficiency of green fluorescent protein

Wed, 11 Nov 2009 18:27:05 -0500

University of California, Berkeley, chemists have discovered the secret to the success of a jellyfish protein whose green glow has made it the darling of biologists and the subject of the 2008 Nobel Prize in Physiology or Medicine.

Longevity tied to genes that preserve tips of chromosomes

Wed, 11 Nov 2009 18:27:03 -0500

A team led by researchers at Albert Einstein College of Medicine of Yeshiva University has found a clear link between living to 100 and inheriting a hyperactive version of an enzyme that rebuilds telomeres – the tip ends of chromosomes. The findings appear in the latest issue of the Proceedings of the National Academy of Sciences.

Scientists decipher the formation of lasting memories

Tue, 10 Nov 2009 15:17:18 -0500

Researchers Researchers at the Swedish medical university Karolinska Institutet have discovered a mechanism that controls the brain's ability to create lasting memories. In experiments on genetically manipulated mice, they were able to switch on and off the animals' ability to form lasting memories by adding a substance to their drinking water. The findings, which are published in the scientific journal PNAS, are of potential significance to the future treatment of Alzheimer's and stroke.

Iowa State University researcher discovers key to vital DNA, protein interaction

Tue, 10 Nov 2009 15:17:17 -0500

A researcher at Iowa State University has discovered how a group of proteins from plant pathogenic bacteria interact with DNA in the plant cell, opening up the possibility for what the scientist calls a "cascade of advances."

Newly discovered fat molecule: An undersea killer with an upside

Mon, 09 Nov 2009 16:55:04 -0500

A chemical culprit responsible for the rapid, mysterious death of phytoplankton in the North Atlantic Ocean has been found by collaborating scientists at Rutgers University and the Woods Hole Oceanographic Institution (WHOI). This same chemical may hold unexpected promise in cancer research.