A new year also means a new edition of MaxWell’s Monthly Must-Reads. This year we have prepared twelve interesting topics for you to read more about. Each month we will highlight one groundbreaking article for you. In addition to this, four related articles are added to the must-reads!

To start off 2020, here are five publications related to the topic of Axons.

The Axon Initial Segment is the Dominant Contributor to the Neuron’s Extracellular Electrical Potential Landscape
by Douglas J. Bakkum, Marie Engelene J. Obien, Milos Radivojevic, David Jackel, Urs Frey, Hirokazu Takahashi and Andreas R. Hierlemann. Advanced Biosystems. November 2018.

When you measure an extracellularly-recorded action potential (EAP) waveform, do you know what you are looking at? Is it the current from the depolarizing cell body? The action potential propagating down the axon? Could it even be the sum of currents running antidromically into the dendritic arbors? In this seminal paper published in the February 2019 issue of Advanced Byosystems, Bakkum and colleagues use high-density microelectrode array (HD-MEA) technology to dissect the shapes, polarities, and amplitudes of extracellular voltage currents measured along the various sub-compartments of single cells in two preparations: (1) cortical cell cultures and (2) cerebellar Purkinje cells in acute brain slices. Contrary to the standard assumption that the main contribution to the EAP comes from the soma, the researchers discovered that the axon initial segment (AIS) gives by far the strongest negative polarity signal, thereby dominating the EAP landscape. The signal initiates at the distal portion of the AIS, spreading to the soma, with a corresponding return current detectable at the dendritic area seen as a positive waveform. This work demonstrates that the unprecedented level of detail in neuronal electrical “footprints” revealed by HD-MEA recordings allows to precisely pinpoint the origin of EAPs, which may give completely different interpretations to results obtained by other classical electrophysiological tools.

Read the paper here.

Besides the above-mentioned paper, four other highly relevant papers concerning the topic of axons can be found below:

  1. Large-Scale Mapping of Axonal Arbors Using High-Density Microelectrode Arrays
    by Torsten Bullmann, Milos Radivojevic, Stefan T. Huber, Kosmas Deligkaris, Andreas Hierlemann and Urs Frey. Frontiers in Cellular Neuroscience. September 2019.
    Read the paper here.
  2. Technologies to Study Action Potential Propagation With a Focus on HD-MEA’s
    by Vishalini Emmenegger, Marie Engelene J. Obien, Felix Franke and Andreas Hierlemann. Frontiers in Cellular Neuroscience. April 2019.
    Read the paper here.
  3. Required growth facilitators propel axon regeneration across complete spinal cord injury
    by Mark A. Anderson, Timothy M. O’Shea, Joshua E. Burda, Yan Ao, Sabry L. Barlatey, Alexander M. Bernstein, Jae H. Kim, Nicholas D. James, Alexandra Rogers, Brian Kato, Alexander L. Wollenberg, Riki Kawaguchi, Giovanni Coppola, Chen Wang, Timothy J. Deming, Zhigang He, Gregoire Courtine and Michael V. Sofroniew. Nature. August 2018.
    Read the paper here. More information can be found here.
  4. Axon-Seq Decodes the Motor Axon Transcriptome and Its Modulation in Response to ALS
    by Jik Nijssen, Julio Aguila, Rein Hoogstraaten, Nigel Kee and Eva Hedlund. CellPress. December 2018.
    Read the paper here. More information can be found here.