Effect of early life knock down of TETs on sex differences in cell type in the hypothalamus

• Autores: Cortes, Laura; Cisternas, Carla Daniela; Golynker, Ilona; Castillo-Ruiz, Alexandra; Forger, Nancy G
• Año de publicación: 2019
• Idioma: inglés
• Tipo de recurso: documento de conferencia
• Materia: Epigenetics; DNA demethylation; Sexual diferentiation; Hypothalamus
• Institución: Universidad Nacional de Córdoba

Fil: Cortes, Laura R. Georgia State University. Neuroscience Institute; USA.
Fil: Cisternas, Carla Daniela. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Biología Celular; Argentina.
Fil: Cisternas, Carla Daniela. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Fisiología Animal; Argentina.
Fil: Cisternas, Carla Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina.
Fil: Golynker, Ilona. Georgia State University; Estados Unidos.
Fil: Castillo-Ruiz, Alexandra. Georgia State University; Estados Unidos.
Fil: Forger, Nancy G. Georgia State University. Neuroscience Institute; USA.
One type of sex difference in the brain involves differences in the number of cells expressing a particular marker. For example, females have more cells expressing estrogen receptor alpha (ERa) in the ventrolateral region of the ventromedial nucleus of the hypothalamus (VMHvl), while males have more cells expressing calbindin in the sexually dimorphic nucleus of the preoptic area (CALB-SDN). DNA methylation and hydroxymethylation are crucial for the differentiation of neuronal cell phenotype during development, and we hypothesize that they may also play a role in the sexual differentiation of cell phenotype. To test this, we first treated newborn mice with zebularine, a global inhibitor of DNA methyl transferases (DNMTs). Zebularine treatment had a lasting effects on the number of cells expressing ERa and calbindin and reduced or eliminated sex differences in these markers (Mosley et al. 2019). DNA methylation and de-methylation are carried out by DNMTs (DNMT1, DNMT3b, and DNMT3a) and TET enzymes (TET1, TET2, TET3), respectively. We find that expression of these enzymes is much higher early in life compared to adulthood, and there are sex differences in the expression of all TETs and of DNMT1. To test whether these sex differences in enzyme expression underlie sex differences in cell phenotype, we used small interfering RNAs (siRNA) down-regulate DNMT1/DNMT3a or TET2/TET3. We found that injecting 2 microliters of 400pmol siRNA into the ventricles of male and female pups on P5 leads to a robust (~40%) down-regulation of expression compared to animals given control siRNA. Animals will be sacrificed at weaning and we will determine whether neonatal DNMT or TET knocknown alters the number of cells expressing ERa in the VMHvl and medial POA and calbindin in the SDN-POA and bed nucleus of the stria terminalis.
https://www.sfn.org/meetings/neuroscience-2019
Fil: Cortes, Laura R. Georgia State University. Neuroscience Institute; USA.
Fil: Cisternas, Carla Daniela. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Biología Celular; Argentina.
Fil: Cisternas, Carla Daniela. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Cátedra de Fisiología Animal; Argentina.
Fil: Cisternas, Carla Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina.
Fil: Golynker, Ilona. Georgia State University; Estados Unidos.
Fil: Castillo-Ruiz, Alexandra. Georgia State University; Estados Unidos.
Fil: Forger, Nancy G. Georgia State University. Neuroscience Institute; USA.
Bioquímica y Biología Molecular (ídem 3.1.10)