RESUMEN
Neuromodulators such as monoamines are often expressed in neurons that also release at least one fast-acting neurotransmitter. The release of a combination of transmitters provides both "classical" and "modulatory" signals that could produce diverse and/or complementary effects in associated circuits. Here, we establish that the majority of Drosophila octopamine (OA) neurons are also glutamatergic and identify the individual contributions of each neurotransmitter on sex-specific behaviors. Males without OA display low levels of aggression and high levels of inter-male courtship. Males deficient for dVGLUT solely in OA-glutamate neurons (OGNs) also exhibit a reduction in aggression, but without a concurrent increase in inter-male courtship. Within OGNs, a portion of VMAT and dVGLUT puncta differ in localization suggesting spatial differences in OA signaling. Our findings establish a previously undetermined role for dVGLUT in OA neurons and suggests that glutamate uncouples aggression from OA-dependent courtship-related behavior. These results indicate that dual neurotransmission can increase the efficacy of individual neurotransmitters while maintaining unique functions within a multi-functional social behavior neuronal network.
Asunto(s)
Agresión , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiología , Neuronas/metabolismo , Transmisión Sináptica/genética , Proteínas de Transporte Vesicular de Glutamato/genética , Animales , Animales Modificados Genéticamente , Conducta Animal , Cortejo , Proteínas de Drosophila/metabolismo , Femenino , Ácido Glutámico/metabolismo , Masculino , Octopamina/metabolismo , Factores Sexuales , Transducción de Señal/genética , Vesículas Sinápticas/metabolismo , Proteínas de Transporte Vesicular de Glutamato/metabolismo , Proteínas de Transporte Vesicular de Monoaminas/metabolismoRESUMEN
L63 encodes a CDK-like protein homologous to the mammalian PFTAIRE. We showed previously that L63 provides a CDK-related function critical to development (Dev. Biol. 221 (2000) 23). We present here the first biochemical characterization of L63 kinase. In addition, we describe two novel Drosophila proteins, PIF-1 and PIF-2 (for PFTAIRE Interacting Factor-1 and -2), identified in a two-hybrid screen for their ability to interact with the amino-terminal region of L63. The full-length PIF-1 cDNA shows an unusual dicistronic organization. PIF-1A and PIF-1B (the L63 interactor) predicted proteins are expressed in vivo, and show a distinct expression profile during development. Interaction between L63 and PIF-1B was confirmed in vitro and in vivo. The role of this interaction remains to be demonstrated, but our data suggest that PIF-1B might serve as a regulator of L63.