Marmosets have a greater diversity ofc-Fosresponse after hyperstimulation in distinct cortical regions as compared to rats
JOURNAL OF COMPARATIVE NEUROLOGY
Authors: Magalhaes, Stefani Alves; Foresti, Maira Licia; Barros, Vanessa Novaes; Mello, Luiz E.
Abstract
Previous evidence indicated a potential mechanism that might support the fact that primates exhibit greater neural integration capacity as a result of the activation of different structures of the central nervous system, as compared to rodents. The current study aimed to provide further evidence to confirm previous findings by analyzing the patterns of c-Fos expression in more neocortical structures of rats and marmosets using a more robust quantitative technique and evaluating a larger number of brain areas. Nineteen Wistar rats and 21 marmosets (Callithrix jacchus) were distributed among control groups (animals without injections) and animals injected with pentylenetetrazol (PTZ) and euthanized at different time points after stimulus. Immunohistochemical detection of c-Fos was quantified using unbiased and efficient stereological cell counting in eight neocortical regions. Marmosets had a c-Fos expression that was notably more widely expressed (5x more cells) and longer lasting (up to 3 hr) than rats. c-Fos expression in rats presented similar patterns of expression according to the function of the brain cortical structures (associative, sensorial, and motor functions), which was not observed for marmosets (in which no clear pattern could be drawn, and a more diverse profile emerged). Our results provide evidence that the marmoset brain has a greater neuronal activation after intense stimulation by means of PTZ and a more complex pattern of brain activation. We speculate that these functional differences may contribute for the understanding of the different neuronal processing capacities of the neocortex in these mammals' orders.
Detecting protein-protein interactions by Xe-129 NMR
CHEMICAL COMMUNICATIONS
Authors: Zhao, Zhuangyu; Roose, Benjamin W.; Zemerov, Serge D.; Stringer, Madison A.; Dmochowski, Ivan J.
Abstract
Detection of protein-protein interactions (PPIs) is limited by current bioanalytical methods. A protein complementation assay (PCA), split TEM-1 beta-lactamase, interacts with xenon at the interface of the TEM-1 fragments. Reconstitution of TEM-1-promoted here by cFos/cJun leucine zipper interaction-gives rise to sensitive(129)Xe NMR signal in bacterial cells.