RT Journal Article
T1 Expression of SATB1 and SATB2 in the brain of bony fishes: what fish reveal about evolution
A1 Lozano Rebollo, Daniel
A1 López Redondo, Jesús María
A1 Jiménez Álvarez, Sara
A1 Morona Arribas, Ruth
A1 Ruiz López, Víctor
A1 Martínez, Ana
A1 Moreno García, Nerea
AB Satb1 and Satb2 belong to a family of homeodomain proteins with highly conserved functional and regulatory mechanismsand posttranslational modifications in evolution. However, although their distribution in the mouse brain has been analyzed, few data exist in other non-mammalian vertebrates. In the present study, we have analyzed in detail the sequence of SATB1 and SATB2 proteins and the immunolocalization of both, in combination with additional neuronal markers of highly conserved populations, in the brain of adult specimens of different bony fish models at key evolutionary points of vertebrate diversification, in particular including representative species of sarcopterygian and actinopterygian fishes. We observed astriking absence of both proteins in the pallial region of actinopterygians, only detected in lungfish, the only sarcopterygian fish. In the subpallium, including the amygdaloid complex, or comparable structures, we identified that the detected expressions of SATB1 and SATB2 have similar topologies in the studied models. In the caudal telencephalon, all models showed significant expression of SATB1 and SATB2 in the preoptic area, including the acroterminal domain of this region, where thecells were also dopaminergic. In the alar hypothalamus, all models showed SATB2 but not SATB1 in the subparaventriculararea, whereas in the basal hypothalamus the cladistian species and the lungfish presented a SATB1 immunoreactive population in the tuberal hypothalamus, also labeled with SATB2 in the latter and colocalizing with the gen Orthopedia. In the diencephalon, all models, except the teleost fish, showed SATB1 in the prethalamus, thalamus and pretectum, whereas only lungfish showed also SATB2 in prethalamus and thalamus. At the midbrain level of actinopterygian fish, the optic tectum, the torus semicircularis and the tegmentum harbored populations of SATB1 cells, whereas lungfish housed SATB2 only inthe torus and tegmentum. Similarly, the SATB1 expression in the rhombencephalic central gray and reticular formation was a common feature. The presence of SATB1 in the solitary tract nucleus is a peculiar feature only observed in non-teleost actinopterygian fishes. At these levels, none of the detected populations were catecholaminergic or serotonergic. In conclusion, the protein sequence analysis revealed a high degree of conservation of both proteins, especially in the functional domains, whereas the neuroanatomical pattern of SATB1 and SATB2 revealed significant differences between sarcopterygians and actinopterygians, and these divergences may be related to the different functional involvement of both in the acquisition of various neural phenotypes.
PB Springer
SN 1863-2653
YR 2023
FD 2023-04-01
LK https://hdl.handle.net/20.500.14352/72423
UL https://hdl.handle.net/20.500.14352/72423
LA eng
NO Ministerio de Ciencia e Innovación (grant no. PID2020- 112681GB100), and the Santander/Complutense University of Madrid, Grant/Award Number: PR108/20-17
NO Universidad Complutense de Madrid (UCM) /Banco de Santander
DS Docta Complutense
RD 17 abr 2025