Nav: Home

Connecting neurons in the brain

May 02, 2019

The brain consists of a large collection of interconnected neurons. How complex patterns of neuronal cells grow into functioning circuits during development has fascinated researchers for decades. A team of scientists at VIB and KU Leuven has now uncovered a new signaling mechanism in fruit flies that specifies the formation of neuronal circuits in the brain.

About 100 billion neurons form a complex and interconnected network in our brain, allowing us to generate complex thought patterns and actions. Neurons come in all sizes and shapes, but they mostly have long protrusions that connect to neighboring cells through specialized information-transmission structures called synapses.

How this intricate network takes shape during early development captivates many neuroscientists, including Prof. Dietmar Schmucker (VIB-KU Leuven) who has built a career studying neuronal wiring. "Proper brain functioning relies on very controlled branching of neuronal cell-extensions called axons and dendrites, and the correct formation of synapses at precise locations along these branches," he says. "Specifying synapse formation determines where and how many potential connections a neuronal cell is "allowed" to form. Therefore, controlling synapse numbers at each neuronal branch is essential for the correct formation of complex brain circuits."

A new player


Schmucker's team turned to the developing fly brain to study which molecular players control synapse formation in specific subcellular compartments. Using a genetic single-cell approach, the researchers could label and manipulate individual neuronal protrusions in the nervous system of the fruit fly, a popular model organism for neuroscientists.

"We found differences in neuronal branching and in synapse numbers at individual protrusions of neurons of the same type," explains Olivier Urwyler a postdoc in the lab, who developed this new experimental system. Urwyler, now a group leader at University Zurich, found that a phosphatase called Prl-1 was decisive for specifying where to form the highest density of synaptic connections on a given neuron.

In fruit flies, loss of Prl-1 led to defects in the formation of neuronal connections in several different circuits, suggesting that this protein phosphatase is of general importance in circuit formation. The team also identified through which signaling pathway Prl-1 exerts its function.

"Surprisingly, it turns out to be one of the most ubiquitously acting signaling pathways, the Insulin receptor/Akt/mTor pathway, required in many physiological responses, cellular growth and cancer, says Urwyler. "Restricting the subcellular protein distribution of Prl-1 to a small compartment results in this potent signaling cascade to locally boost synapse formation."

From flies to humans?


Flies that lack Prl-1 show severe locomotor problems. Interestingly, if Prl-1 is erroneously overexpressed and out of control, it can drive metastatic behavior of cancer cells.

As Prl-1 phosphatases are conserved from invertebrates to mammals, what could this imply for humans? According to Schmucker, their presence in different regions of the human brain means that Prl-1 phosphatases are poised to function in a similar way during vertebrate brain development:

"The compartmentalized restriction of Prl-1 could serve as a specificity factor to control the precise tuning of synaptic connections in human neurons as well, similar to the effects we have shown for the assembly of neuronal circuits and synapses in fruit flies."
-end-
Publication

Prl-1 phosphatase directs compartmentalized control of InR/Akt signaling during CNS synapse formation, Urwyler et al., Science 2019

Questions from patients

A breakthrough in research is not the same as a breakthrough in medicine. The realizations of VIB researchers can form the basis of new therapies, but the development path still takes years. This can raise a lot of questions. That is why we ask you to please refer questions in your report or article to the email address that VIB makes available for this purpose: patienteninfo@vib.be. Everyone can submit questions concerning this and other medically-oriented research directly to VIB via this address.

VIB (the Flanders Institute for Biotechnology)

Related Neurons Articles:

The first 3D map of the heart's neurons
An interdisciplinary research team establishes a new technological pipeline to build a 3D map of the neurons in the heart, revealing foundational insight into their role in heart attacks and other cardiac conditions.
Mapping the neurons of the rat heart in 3D
A team of researchers has developed a virtual 3D heart, digitally showcasing the heart's unique network of neurons for the first time.
How to put neurons into cages
Football-shaped microscale cages have been created using special laser technologies.
A molecule that directs neurons
A research team coordinated by the University of Trento studied a mass of brain cells, the habenula, linked to disorders like autism, schizophrenia and depression.
Shaping the social networks of neurons
Identification of a protein complex that attracts or repels nerve cells during development.
With these neurons, extinguishing fear is its own reward
The same neurons responsible for encoding reward also form new memories to suppress fearful ones, according to new research by scientists at The Picower Institute for Learning and Memory at MIT.
How do we get so many different types of neurons in our brain?
SMU (Southern Methodist University) researchers have discovered another layer of complexity in gene expression, which could help explain how we're able to have so many billions of neurons in our brain.
These neurons affect how much you do, or don't, want to eat
University of Arizona researchers have identified a network of neurons that coordinate with other brain regions to influence eating behaviors.
Mood neurons mature during adolescence
Researchers have discovered a mysterious group of neurons in the amygdala -- a key center for emotional processing in the brain -- that stay in an immature, prenatal developmental state throughout childhood.
Connecting neurons in the brain
Leuven researchers uncover new mechanisms of brain development that determine when, where and how strongly distinct brain cells interconnect.
More Neurons News and Neurons Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Making Amends
What makes a true apology? What does it mean to make amends for past mistakes? This hour, TED speakers explore how repairing the wrongs of the past is the first step toward healing for the future. Guests include historian and preservationist Brent Leggs, law professor Martha Minow, librarian Dawn Wacek, and playwright V (formerly Eve Ensler).
Now Playing: Science for the People

#565 The Great Wide Indoors
We're all spending a bit more time indoors this summer than we probably figured. But did you ever stop to think about why the places we live and work as designed the way they are? And how they could be designed better? We're talking with Emily Anthes about her new book "The Great Indoors: The Surprising Science of how Buildings Shape our Behavior, Health and Happiness".
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.