There are rules governing which types of connections should be established, although it remains unclear how neurons ‘know’ these rules. “Recognition seems to occur because neurons are always connected with [the] right partners, but the real mechanisms for this recognition remain unknown—and it is even unclear whether such ‘recognition’ really takes place,” explains Masatoshi Takeichi of the RIKEN Center for Developmental Biology in Kobe.
The cerebellum primarily receives inputs from two kinds of axonal fibers: mossy fibers, originating from pontine nuclei in the cerebral cortex, and climbing fibers, which emerge from inferior olivary nuclei in the medulla. Each of these fiber types in turn associates with a specific subset of cerebellar cells; mossy fibers form synapses with granule cells (GCs), while climbing fibers connect to Purkinje cells.
Prior data indicate that these various cells interact indiscriminately early in development but then abort inappropriate connections as the brain matures, and Takeichi and graduate student Shoko Ito recently explored this phenomenon in the context of studying how cerebellar GCs find the right partner (1).
Co-cultures of GCs with pontine tissue showed little evidence of specific interaction between cells at first, but within several days began to exhibit signs of synapse formation. Interestingly, time-lapse movies revealed that dendrites from GCs appear capable of specifically recognizing mossy fibers, forming claw-like structures that physically latch onto these axons.
GCs showed markedly different behavior when cultured with climbing fibers or hippocampal cells, forming connections that displayed some characteristics of working synapses, but without the full range of morphological changes observed in dendrites from the pontine co-cultures. “Granule cells could form synapses with the correct positioning and morphology only when they met the mossy fibers,” says Takeichi. “This finding was unexpected.”
Overall, these findings suggest that although cerebellar cells can forge tentative links with a diverse array of axons, specific recognition mechanisms are in place to ensure proper synaptic wiring. “We have convincingly demonstrated that neurons do recognize their specific partners even in vitro, where environmental cues which could assist neuronal recognition are absent,” says Takeichi. Exactly which factors facilitate this recognition remains a mystery, however, and he indicates that this will be a focus of future research from his laboratory.
The corresponding author for this highlight is based at the Laboratory for Cell Adhesion and Tissue Patterning, RIKEN Center for Developmental Biology
Saeko Okada | Research asia research news
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
25.06.2018 | Ecology, The Environment and Conservation
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences