RESUMO
BACKGROUND: A common feature of memory and its underlying synaptic plasticity is that each can be dissected into short-lived forms involving modification or trafficking of existing proteins and long-term forms that require new gene expression. An underlying assumption of this cellular view of memory consolidation is that these different mechanisms occur within a single neuron. At the neuroanatomical level, however, different temporal stages of memory can engage distinct neural circuits, a notion that has not been conceptually integrated with the cellular view. RESULTS: Here, we investigated this issue in the context of aversive Pavlovian olfactory memory in Drosophila. Previous studies have demonstrated a central role for cAMP signaling in the mushroom body (MB). The Ca(2+)-responsive adenylyl cyclase RUTABAGA is believed to be a coincidence detector in gamma neurons, one of the three principle classes of MB Kenyon cells. We were able to separately restore short-term or long-term memory to a rutabaga mutant with expression of rutabaga in different subsets of MB neurons. CONCLUSIONS: Our findings suggest a model in which the learning experience initiates two parallel associations: a short-lived trace in MB gamma neurons, and a long-lived trace in alpha/beta neurons.
Assuntos
Adenilil Ciclases/fisiologia , AMP Cíclico/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/fisiologia , Memória/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , Adenilil Ciclases/deficiência , Adenilil Ciclases/genética , Animais , Animais Geneticamente Modificados , Aprendizagem da Esquiva/fisiologia , Condicionamento Clássico/fisiologia , Proteínas de Drosophila/deficiência , Proteínas de Drosophila/genética , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Feminino , Técnicas de Inativação de Genes , Teste de Complementação Genética , Masculino , Memória de Curto Prazo/fisiologia , Corpos Pedunculados/citologia , Neurônios/classificação , Mutação Puntual , Proteínas Recombinantes de Fusão/fisiologia , Retenção Psicológica/fisiologia , Olfato/fisiologiaRESUMO
4-Aryl-substituted N-thiolated beta-lactams are a new family of antibacterial agents possessing unique structure-activity profiles and a mode of action. Unlike traditional beta-lactam antibiotics, which require highly polar enzyme-binding groups, these lactams bear hydrophobic groups on their side chains. In this study, we examine the effect that increasing hydrophobicity, through fluorine substitution in the C(4) aryl ring, has on the antibacterial properties.
