RESUMO
Epitranscriptomic mechanisms linking tRNA function and the brain proteome to cognition and complex behaviors are not well described. Here, we report bi-directional changes in depression-related behaviors after genetic disruption of neuronal tRNA cytosine methylation, including conditional ablation and transgene-derived overexpression of Nsun2 in the mouse prefrontal cortex (PFC). Neuronal Nsun2-deficiency was associated with a decrease in tRNA m5C levels, resulting in deficits in expression of 70% of tRNAGly isodecoders. Altogether, 1488/5820 proteins changed upon neuronal Nsun2-deficiency, in conjunction with glycine codon-specific defects in translational efficiencies. Loss of Gly-rich proteins critical for glutamatergic neurotransmission was associated with impaired synaptic signaling at PFC pyramidal neurons and defective contextual fear memory. Changes in the neuronal translatome were also associated with a 146% increase in glycine biosynthesis. These findings highlight the methylation sensitivity of glycinergic tRNAs in the adult PFC. Furthermore, they link synaptic plasticity and complex behaviors to epitranscriptomic modifications of cognate tRNAs and the proteomic homeostasis associated with specific amino acids.
Assuntos
Transtorno Depressivo/fisiopatologia , Epigênese Genética/genética , Metiltransferases/genética , Proteoma/metabolismo , RNA de Transferência/genética , Transmissão Sináptica/genética , Animais , Transtorno Depressivo/genética , Transtorno Depressivo/metabolismo , Perfilação da Expressão Gênica/métodos , Metiltransferases/deficiência , Metiltransferases/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Neurônios/metabolismo , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiologia , Proteômica/métodos , RNA de Transferência/metabolismo , Transdução de Sinais/genéticaRESUMO
AIM: To our knowledge, the relationship between simple renal cysts, hypertension and three significant genes of the renin-angiotensin system (AGT, AT1R and ACE1) has not been studied. The present study was designed to search for possible relationships between these significant polymorphic components, hypertension and simple renal cysts in Shiraz province (Iran). METHODS: A total of 160 participants were recruited from the Motahari Clinic at Shiraz University of Medical Sciences. The subjects were divided into four main groups. Detection of the ACE1 genotype was performed with a nested-polymerase chain reaction (PCR) protocol. Two separate restriction fragment length polymorphism-PCR assays were used to identify AGT and AT1R genotypes. RESULTS: The allele frequency of AGT M235T differed significantly between group 1 (patients with simple renal cysts and hypertension) and normal individuals (p < 0.05). There were no significant differences in frequency for the other genes (ACE1 and AT1R). CONCLUSIONS: Our findings show a relationship between the AGT-TT genotype and hypertension in patients with both hypertension and simple renal cysts. This finding suggests an additive role for the AGT gene of the renin-angiotensin system in the process of hypertension and simple renal cysts formation. Future studies are needed to elucidate the mechanisms through which this association is mediated.
Assuntos
Angiotensinogênio/genética , Etnicidade/genética , Predisposição Genética para Doença , Hipertensão/genética , Doenças Renais Císticas/genética , Polimorfismo Genético , Eletroforese em Gel de Ágar , Frequência do Gene/genética , Humanos , Hipertensão/complicações , Irã (Geográfico) , Doenças Renais Císticas/complicações , Pessoa de Meia-Idade , Peptidil Dipeptidase A/genética , Receptor Tipo 1 de Angiotensina/genéticaRESUMO
BACKGROUND: Male pattern baldness or androgenetic alopecia is a common disorder affecting almost 50% of men throughout their lifetime, with androgens and genetics having significant contributing aetiologies. In contrast to the positive regulatory effect of androgens on body hair growth, they are thought to alter scalp hair follicle behaviour pathophysiologically, leading to male pattern baldness. However, the exact mechanisms of this paradoxical action have not yet been elucidated. The role of microRNAs, a novel group of noncoding RNAs impacting almost every aspect of biology, health and human diseases, has been documented in hair follicle formation. In addition, their deregulation in cancer of the prostate, a target organ of androgens, has also been well established. OBJECTIVES: To investigate the possible contribution of microRNAs in the pathophysiology of male pattern baldness. METHODS: We initially screened microRNA expression profiles of balding and nonbalding hair follicle papillae with a sensitive microRNA cloning method, microRNA amplification profiling, and statistically analysed significant differentially expressed microRNAs in balding relative to nonbalding dermal papillae, with real-time polymerase chain reaction as a confirmatory method to quantify expression in eight individuals affected with the disorder. RESULTS: We detected the significant upregulation of miR-221, miR-125b, miR-106a and miR-410 in balding papilla cells. CONCLUSIONS: We found four microRNAs that could participate in the pathogenesis of male pattern baldness. Regarding the strong therapeutic potential of microRNAs and the easy accessibility of hair follicles for gene therapy, microRNAs are possible candidates for a new generation of revolutionary treatments.