synapse

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As Virginia Hughes noted in a recent piece for National Geographic’s Phenomena blog, the most common depiction of a synapse (that communicating junction between two neurons) is pretty simple:

External image

Signal molecules leave one neuron from that bulby thing, float across a gap, and are picked up by receptors on the other neuron. In this way, information is transmitted from cell to cell … and thinking is possible.

But thanks to a bunch of German scientists - we now have a much more complete and accurate picture. They’ve created the first scientifically accurate 3D model of a synaptic bouton (that bulby bit) complete with every protein and cytoskeletal element.

This effort has been made possible only by a collaboration of specialists in electron microscopy, super-resolution light microscopy (STED), mass spectrometry, and quantitative biochemistry.

says the press release. The model reveals a whole world of neuroscience waiting to be explored. Exciting stuff!

You can access the full video of their 3D model here.

Credit: Benjamin G. Wilhelm, Sunit Mandad, Sven Truckenbrodt, Katharina Kröhnert, Christina Schäfer, Burkhard Rammner, Seong Joo Koo, Gala A. Claßen, Michael Krauss, Volker Haucke, Henning Urlaub, Silvio O. Rizzoli

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The emotional sensitivity gene

Serotonin is one of the major neurotransmitters (i.e. chemicals) in the brain. It’s very connected to our emotions and so it’s not a coincidence that a lot of the drugs that are used to treat depression and anxiety act on the serotonin system in the brain. This is clearly a very important chemical for determining the nature of our emotional lives.

The serotonin transporter gene regulates serotonin in the brain. People are born with variations of this gene. The long variation clears serotonin out of the neural synapse more efficiently. The short variation is less efficient, which lets the serotonin hang around a little bit longer in the synapse. 

The short variation was originally considered a risk gene — but it’s now being thought of as a sensitivity gene.

Learn more about how the gene impacts our emotional responses →

Incredible and rare micrograph of a synapse 

Neuron cell body (purple) with numerous synapses (blue) magnified 80,000x under a scanning electron microscope.

Everone talks about synapses even though some seem to use it to sound cool without actually knowing what it is. So for those persons (and everyone willing to become a bit more educated), here’s a simple explanation.

Information from one neuron flows to another neuron across a synapse. The synapse contains a small gap separating neurons. 

The synapse consists of:

a presynaptic ending that contains neurotransmitters, mitochondria and other cell organelles,

a postsynaptic ending that contains receptor sites for neurotransmitters,

a synaptic cleft or space between the presynaptic and postsynaptic endings.

At the synaptic terminal (the presynaptic ending), an electrical impulse will trigger the migration of vesicles containing neurotransmitters toward the presynaptic membrane. The vesicle membrane will fuse with the presynaptic membrane releasing the neurotransmitters into the synaptic cleft. 

read more from Neurons Want Food 

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Gary Carlson  
Medical and Biological Illustration
[website]

OSTEOCLAST ACTIVITY
Osteoclasts remove excess bone by etching away at the bone surface. When they become overactive, osteoporosis may occur. [source]

ADIPOGENESIS
Adipocytes, or fat cells, greatly increase in size over time as lipid droplets accumulate within the cytoplasm.  [source]

SYNAPTIC JUNCTION
Schematic representation of neurotransmitters crossing between neurons showing the action of a drug for treating Alzheimer’s disease.[source]