The images show how an embryo develops cartilage that is later calcified turning into bone. Researchers stained embryos with dyes (green & red) to show the calcium compounds in bone and sugar in cartilage. [Via cen.chempics.org]
Expression of combinations of three different fluorescent proteins in a mouse brain produced ten different colored neurons. Individual neurons in a mouse brain appear in different colors in a fluorescence microscope. This “Brainbow” method enables many distinct cells within a brain circuit to be viewed at one time.
Scientists are one step closer to understanding the genetic difference between human and chimpanzee brain development. They isolated a stretch of DNA, once thought to be “junk”, near a gene that regulates brain development. Then they added that DNA – either the human or the chimp version – to mouse embryos. Lo and behold, the mouse brains with human DNA were 12% bigger than mouse brains with chimpanzee DNA.
Eventually, work like this could generate a list of DNA sequences that give a brain some capabilities that are characteristically human. That could be important for understanding what goes wrong in diseases of the
As for the ethics of such experiments:
An experiment like this recent one is not going to create mice that talk and think like people. But it could be more ethically
worrisome to try to genetically enhance the brains of nonhuman primates
or other reasonably intelligent animals — like pigs.
This mouse kidney growing in the laboratory reveals how a molecule
called beta-catenin instructs the organ to develop: the areas in yellow
show where the molecule is most active. Copyright: Dr Nils Lindstrom,
University of Edinburgh
WHAT IS IT? The hippocampus is found deep in the brains of many mammals, including humans. It’s named for its seahorse shape (in Greek, hippokampos literally means “horse sea monster”).
WHY IS IT IMPORTANT? It helps us form memories and navigate space. It contains special cells called “place cells” that create a mental map of our environment. The hippocampus is also one of the first structures to suffer in patients with Alzheimer’s disease, which is characterized by memory loss. The number of patients with Alzheimer’s is predicted to triple by 2050.
WHERE DO WE GO FROM HERE? Scientists at Harvard Medical School were recently able to re-create Alzheimer’s disease from human cells in a culture dish. This will “revolutionize drug discovery in terms of speed, costs and [disease relevance],” according to a senior co-author on the study.
Image by Chris Henstridge/MTA-KOKI/Nikon Small World.