The retina of the eye, which is part of the central nervous system, is where visual impressions take their initial shape. The retina consists of photoreceptors and several different specialized nerve cells that use various networks to coordinate impressions from the light-sensitive photoreceptors before the information is relayed to the brain.
Per-Henrik Edqvist has studied how the retina’s complex structure of specialized cells is formed from a small number of retina stem cells during the fetal development of chickens.
Above all, he has examined how one of the retina’s specialized cell types, so-called horizontal cells, are formed and reach maturity. Their task is to receive and integrate information from a large number of photoreceptors, and there are at least two functionally different types.
“We have characterized the molecular development of these different horizontal cell types in order to better understand how the nervous system is formed,” explains Per-Henrik Edqvist.
He shows that the different types take on their determined role at a very early stage in development, which conflicts with certain conventional models of the development of the retina. What’s more, they do not develop simultaneously but rather one after the other, and in their development they undergo a highly unexpected cell migration from their birth site to their ultimate position in the retina.
“The fact that they migrate at different times toward or away from signals that can influence their continued development may be the mechanism that governs them in different developmental directions,” says Per-Henrik Edqvist.
The dissertation enhances our knowledge of how the central nervous system is formed during fetal development, and thereby our understanding of how disturbances of the brain and ocular system can occur and be prevented.
“By understanding these mechanisms, we hope some day to be able to use stem cells to create spare parts that can replace damaged or dead nerve cells in the retina.”
Anneli Waara | alfa
Cholesterol-lowering drugs may fight infectious disease
22.08.2017 | Duke University
Once invincible superbug squashed by 'superteam' of antibiotics
22.08.2017 | University at Buffalo
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
22.08.2017 | Health and Medicine
22.08.2017 | Materials Sciences
22.08.2017 | Life Sciences