RT Journal Article
T1 Pax6 and Pax7 in the central nervous system of cladistian fishes: a comprehensive expression analysis
A1 Lozano Rebollo, Daniel
A1 Chinarro Sánchez, Adrián
A1 Yanguas, Lucía
A1 Morona Arribas, Ruth
A1 Moreno García, Nerea
A1 López Redondo, Jesús María
AB Among actinopterygian fishes, cladistians stand as the more basal extant species in the group, holding a key phylogenetic position close to the common ancestor of Osteichthyes. Despite the recent publication of studies regarding the neurochemical organization of their central nervous system (CNS), there is still a significant lack of genoarchitectonic data that may prove essential to fully understand the patterning of the brain of these fishes. The paired box genes Pax6 and Pax7 are known to determine several boundaries in the CNS and are indispensable, for instance, for the survival of neurons and the change from cell proliferation to cell differentiation. By means of immunohistofluorescence methods, we analyzed the expression patterns of the transcription factors Pax6 and Pax7 in the CNS of three representative species of cladistian fishes, with a particular focus on their evolutionary implications. Thus, conserved Pax6 immunoreactive cell groups were present in the olfactory bulb, subpallial areas, the prethalamus, the basal prosomere 3, the pretectum, the mesencephalic tegmentum, the cerebellum, the basal rhombencephalon, the spinal cord, and the retina. A number of exclusive features were identified, including the almost total absence of expression in the pallium, which was observed only in cladistians, and its absence in the hypothalamus, which is a primitive anamniote trait. Likewise, the Pax7 expression pattern was generally conserved, with traits like the absence of labeling in the telencephalon and the expression in the retromamillary hypothalamic domain, the basal prosomere 3, the pretectum, the optic tectum, and the alar part of the first rhombomere. Additionally, no Pax7 labeling was detected in the spinal cord, comprising a specific cladistian feature.
PB Wiley
SN 0021-9967
YR 2025
FD 2025-04
LK https://hdl.handle.net/20.500.14352/120925
UL https://hdl.handle.net/20.500.14352/120925
LA eng
NO Lozano, D., Chinarro, A., Yanguas, L., Morona, R., Moreno, N. and López, J.M. (2025), Pax6 and Pax7 in the Central Nervous System of Cladistian Fishes: A Comprehensive Expression Analysis. J Comp Neurol, 533: e70053. https://doi.org/10.1002/cne.70053
NO Funding: This work was supported by PID2023-147228NB-I00 and funded by MCIN/AEI/10.13039/501100011033.
NO Ministerio de Ciencia e Innovación (España)
NO Agencia Estatal de Investigación
DS Docta Complutense
RD 6 jul 2025