Browsing by Author "Colicos, Michael A."

Now showing 1 - 6 of 6
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    Activity-dependent subcellular cotrafficking of the small GTPase Rem2 and Ca2+/CaM-dependent protein kinase IIα
    (PLOS one, 2012-07-18) Bernier, Nikolas; De Koninck, Paul; Flynn, Robyn E.; Labrie-Dion, Étienne; Colicos, Michael A.; Zamponi, Gerald W.
    Rem2 is a small monomeric GTP-binding protein of the RGK family, whose known functions are modulation of calcium channel currents and alterations of cytoskeletal architecture. Rem2 is the only RGK protein found predominantly in the brain, where it has been linked to synaptic development. We wished to determine the effect of neuronal activity on the subcellular distribution of Rem2 and its interacting partners.
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    Cell Line Specific Modulation of Extracellular Aβ42 by Hsp40
    (Public Library of Science, 2012-05-29) Carnni, Anna; Scott, Lucas O. M.; Ahrendt, Eva; Proft, Juliane; Winkfein, Robert J.; Kim, Sung-Woo; Colicos, Michael A.; Braun, Janice E. A.
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    Heterogenous Change in Neuronal Bursts Following Recovery from Activity Silencing
    (2018-08-02) Kipp, Alexander Joseph; Colicos, Michael A.; Turner, Ray W.; Davidsen, Jörn
    Silencing of activity in hippocampal neuronal cultures was used to study how dynamic neuronal activity achieves a state of homeostasis, using calcium imaging to detect neuronal firing patterns. Recovering cultures were found to display abnormal activity patterns after 48hrs of exposure to tetrodotoxin, as indicated by paradoxical spike and correlation statistics. It was found that the cultures recovering from activity silencing did not resemble a neuronal system with enhanced excitation, but differed significantly from control experiments. Using a newly developed measure of homogeneity it was found that activity patterns in cultures recovering from silencing were more heterogeneous during bursts, which is in contrast to the current perception that bursting activity is a homogeneous event. It was also observed that there were more active neurons during the recovery period. It is hypothesized that these changes in neuronal system dynamics are brought about due to the insertion and heterogenous manipulation of silent synapses. Results suggest a mechanism through which the interplay between homeostatic scaling, silent synapses and bursting behavior could mediate neuronal network homeostasis.
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    Polarization Controlled Coherent Anti-Stokes Raman Scattering Microscopy for Determination of Structural Order of the Myelin Sheath
    (2018-05-17) Brideau, Craig; Stys, Peter K.; Frayne, Richard; Barclay, Paul; Colicos, Michael A.; Fear, Elise C.; Potma, Eric Olaf
    Coherent Anti-Stokes Raman Scattering (CARS) is a laser-scanning microscopy technique that generates a strong label-free signal in lipid. The myelin sheath surrounding nerves is up to 80% lipid, and therefore is an ideal candidate for CARS imaging. The long lipid chains forming the myelin wraps have a directional preference when the myelin is healthy, with CH2 bonds aligned parallel to the axis of the nerve. The optical polarization dependence of the CARS signal can be used to probe the orientation of CH2 bonds in the sheath and determine their nanoscopic orientation. As myelin becomes unhealthy the organization of the lipids begins to loosen from their native organized packing structure. In the early stages this is not visible by conventional microscopy, however polarization-resolved CARS can measure the increasing disorder in the arrangement of the bonds before obvious morphological changes can occur. The degree of disorder is also measured to provide a metric of myelin disorganization in disease models.
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    The role of neuroligin in synaptic remodeling
    (2010) Gutierrez Herrera, Rosario Carolina; Colicos, Michael A.