DCX and PSA-NCAM expression identifies a population of neurons preferentially distributed in associative areas of different pallial derivatives and vertebrate species.
In adult rodents, doublecortin (DCX) and polysialylated neural cell adhesion molecule (PSA-NCAM) expression is mostly restricted to newly generated neurons. These molecules have also been described in prenatally generated cells of the piriform cortex and, to a lesser extent, neocortex (NC) of the rat. In addition, PSA-NCAM+ cells have been identified in several telencephalic regions of the lizard. Here, through immunohistochemistry and 3-dimensional reconstruction, we have investigated distribution, morphology, and phenotype of DCX/PSA-NCAM-expressing cells in the pallium of different mammals and in lizard. In all species, a population of nonnewly-generated pallial DCX+/PSA-NCAM+ cells shows common morphological and phenotypic characteristics, including expression of Tbr-1, a transcription factor expressed in pallial projection neurons, and preferential distribution in associative areas. In the guinea pig and rabbit, DCX+/PSA-NCAM+ elements are also abundant in the NC, particularly in areas implicated in nonspatial learning and memory networks. In reptiles, DCX+/PSA-NCAM+ cells are located in the lateral and medial cortex and dorsal ventricular ridge but not in the dorsal cortex. These data support the fact that coexpression of DCX+/PSA-NCAM+/Tbr-1+ in the adult brain identifies evolutionary conserved cell populations shared by different pallial derivatives including the mammalian NC.
Luzzati
Federico
F
Department of Animal and Human Biology, University of Turin, Via Accademia Albertina 13, 10153 Turin, Italy. federico.luzzati@unito.it
Bonfanti
Luca
L
Fasolo
Aldo
A
Peretto
Paolo
P
D000818:Animals; D001245:Association Learning / Q000502:physiology; D005075:Biological Evolution; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D005260:Female; D006168:Guinea Pigs; D008116:Lizards; D008297:Male; D008568:Memory / Q000502:physiology; D051379:Mice; D008815:Mice, Inbred Strains; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D039842:Neural Cell Adhesion Molecule L1 / Q000378:metabolism*; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D012794:Sialic Acids / Q000378:metabolism*; D013045:Species Specificity; D013687:Telencephalon / Q000166:cytology* / Q000378:metabolism*; D014714:Vertebrates
C000714328:DCX protein, human; C000714847:Dcx protein, mouse; C000714848:Dcx protein, rat; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D039842:Neural Cell Adhesion Molecule L1; D009479:Neuropeptides; D012794:Sialic Acids; C103469:polysialyl neural cell adhesion molecule