Project description:Brain aromatase, an enzyme responsible for the local synthesis of estrogens, plays a key role in regulating behavior and neuroplasticity in mammals. In teleost fish, brain aromatase is encoded by the cyp19a1b gene, which is strongly expressed in radial glial cells but the specific functions of this enzyme are currently unknown. To investigate its role, a cyp19a1b-mutant zebrafish line was generated using gene-editing techniques. Behavioral, neurogenic, and neurotransmission-related parameters were assessed in adult male and female zebrafish. Behavioral analysis highlighted significant alterations in mutant zebrafish including changes in swimming activity, boldness, sociability, and aggression with a stronger effect in males compared to females. Beyond these behavioral modifications, mutant zebrafish exhibited disrupted cell proliferation patterns, as assessed by PCNA immunofluorescence in key forebrain regions. Specifically, proliferation decreased in the telencephalon and in the caudal hypothalamus of mutant zebrafish while increasing in the olfactory bulbs. The number of dopaminergic and serotonergic neurons, visualized by immunofluorescence, remained unchanged. Similarly, HPLC-ED quantification of monoamines and their metabolites showed no significant differences between mutant and wild-type zebrafish. To further explore the impact of cyp19a1b mutation on gene expression, transcriptomic analysis was performed using BRBSeq technology. Gene expression analyses identified several processes affected by the mutation, including cell proliferation, apoptosis, estrogen signaling, neuroplasticity, and behavioral regulation, in a sex- and region-dependent manner. In conclusion, our results demonstrate that several behaviors, including locomotor activity, sociability, aggressiveness, and anxiety, exhibit marked sexual dimorphism. They show that cyp19a1b mutation affects locomotor activity in a context-dependent manner, increases boldness, and reduces aggressiveness. In addition, transcriptomic analyses revealed widespread dysregulation of gene expression, which likely contributes to the observed behavioral alterations. Taken together, these findings underscore the crucial role of brain aromatase in neurobiological regulation of diverse behaviors.
Project description:Coilin is a nuclear protein known for its roles in assembling the Cajal Body and participating in the biogenesis of ribonucleoproteins. We have uncovered novel functions for coilin in promoting microRNA biogenesis and the phosphorylation/SUMOylation of various proteins, through which we have observed a role for coilin in responding to stress signals. Coilin has also been found to participate in the stress response in plants through the regulated expression of immunity genes and activation of defense mechanisms. In this study, we further investigated this role of coilin in regulating the immune response by applying transcriptomic analyses to examine the response to lipopolysaccharide-mediated stress in coilin-depleted human cells and coilin mutant zebrafish embryos. Our results indicate a vital function for coilin in regulating the expression of immunity-related genes and establish a conserved role for vertebrate coilin in the promotion of the innate immune response across humans and zebrafish.