Expression of the neocortical marker, RORβ, in the entopallium and field L2 of adult chicken.
Two opposing hypotheses on the homology of the avian brain suggest that the dorsal ventricular ridge of birds is comparable in certain respects either to the neocortex or to the claustroamygdalar complex of mammals. To help resolve this issue, we examined in adult chicken brains the gene expression of RORβ mRNA, a selective marker for layer IV of mammalian neocortex. RORβ mRNA was expressed in neurons of the chicken's visual entopallium and auditory field L2, but not in other regions of the nidopallium, hyperpallium, mesopallium or arcopallium. Together with hodological evidence of direct thalamic projections conveying primary sensory information to the entopallium and field L2, our results support the contention that these two regions are composed of neurons comparable to those in layer IV of mammalian neocortex.
Laboratory of Veterinary Anatomy, Faculty of Applied Biological Sciences, Gifu University, Japan. atozi@gifu-u.ac.jp
Yasuro
Y
Atoji
Mohammad Rabiul
MR
Karim
D000595:Amino Acid Sequence; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002645:Chickens; D005260:Female; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D019579:Neocortex / Q000378:metabolism; D057095:Nuclear Receptor Subfamily 1, Group F, Member 2 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D013687:Telencephalon / Q000378:metabolism*
D015415:Biomarkers; D057095:Nuclear Receptor Subfamily 1, Group F, Member 2; D012333:RNA, Messenger