Abstract
CD40-activated CD40L reverse signaling is a major physiological regulator of neural process growth from many kinds of developing neurons. Here we have investigated whether CD40L-reverse signaling also influences dendrite spine number and morphology in striatal medium spiny neurons (MSNs). Golgi preparations revealed no differences in the spine density, but because the dendrite arbors of MSNs were larger and branched in Cd40–/– mice, the total number of spines was greater in Cd40–/– mice. We also detected more mature spines compared with wild-type littermates. Western blot revealed that MSN cultures from Cd40–/– mice had significantly less PSD-95 and there were changes in RhoA/B/C and Cdc42. Immunocytochemistry revealed that PSD-95 was clustered in spines in Cd40–/– neurons compared with more diffuse labeling in Cd40+/+ neurons. Activation of CD40L-reverse signaling with CD40-Fc prevented the changes observed in Cd40–/– cultures. Our findings suggest that CD40L-reverse signaling influences dendrite spine morphology and related protein expression and distribution.
Highlights
Spines are small dynamic protrusions along the dendrites of many kinds of neurons that indicate the location of excitatory synapses
We observed alterations in the number and type of spines in Cd40−/− mice. These morphological modifications were accompanied by changes in the expression of proteins that have been implicated in determining dendrite spine morphology, namely, postsynaptic density (PSD)-95 and the Rho small GTPases RhoA/B/C and Cdc42
Our findings suggest that CD40L reverse signaling regulates the expression and distribution of proteins implicated in governing spine morphology
Summary
Spines are small dynamic protrusions along the dendrites of many kinds of neurons that indicate the location of excitatory synapses. We have investigated whether CD40L reverse signaling influences MSN dendrite spine number and morphology. These morphological modifications were accompanied by changes in the expression of proteins that have been implicated in determining dendrite spine morphology, namely, PSD-95 and the Rho small GTPases RhoA/B/C and Cdc42.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
