![pc1d help pc1d help](https://www.coursehero.com/thumb/16/72/167261ce5d7d9e08c05fb7633764507e440d3b39_180.jpg)
Additionally, social isolation can increase aggression in both male and female flies ( Hoffmann, 1990 Ueda and Kidokoro, 2002). While male aggression is heightened in the presence of mate-related cues, female flies display increased aggressive behaviors when nutrients are limited and near egg laying sites ( Bath et al., 2017 Bath et al., 2018 Lim et al., 2014 Shelly, 1999 Ueda and Kidokoro, 2002). Since the first observation of aggressive behaviors in Drosophila by Sturtevant in 1915, social behaviors associated with attack and threat displays in flies have been well described ethologically ( Shelly, 1999 Sturtevant, 1915 Ueda and Kidokoro, 2002 Zwarts et al., 2012). Additionally, the VMHvl has been implicated in other female sexual behaviors ( Hashikawa et al., 2017 Lee et al., 2014 Pfaff and Sakuma, 1979a Pfaff and Sakuma, 1979b Yang et al., 2013), further complicating the identification of the specific cell types that mediate aggressive interactions.
![pc1d help pc1d help](https://slidetodoc.com/presentation_image_h/88e45fe76e3e0683216645938ab437cc/image-10.jpg)
![pc1d help pc1d help](https://media.cheggcdn.com/media/5b6/5b672301-1e92-4552-9e0b-cd2247d65ce9/phpZbWpcZ.png)
While Esr1 + neurons in the VMHvl regulate aggression in both male and female mice, there are sex differences in the populations involved ( Hashikawa et al., 2017). Recent work using opto- and chemo-genetic techniques have narrowed down these key regions to small populations of cells in mice, including those expressing estrogen receptor alpha (Esr1) and progesterone receptor (PR) in the ventrolateral part of the ventromedial hypothalamus (VMHvl) ( Hashikawa et al., 2017 Lee et al., 2014 Yang et al., 2013). Such key regions are thought to perform a different role than other brain areas that facilitate aggressive interactions by altering the overall level of social behavior ( Siegel et al., 1999). However, understanding the neuronal mechanisms by which such stimuli influence aggression has been hindered by a lack of knowledge about the structure of the underlying neuronal circuits, particularly in females.Ĭenters mediating, or conveying the information necessary for, aggression have been identified in the medial hypothalamus through classic experiments using electrical stimulation in cats and rodents ( Albert et al., 1979 Bandler et al., 1972 Berntson, 1973 Chi and Flynn, 1971 Gregg, 2003 Kruk et al., 1983 Lammers et al., 1988 Siegel et al., 1999 Takahashi and Miczek, 2014 Woodworth, 1971). Sensory information about the presence of other individuals and the nature of the surrounding environment strongly modulate aggressive social interactions ( Chen and Hong, 2018 Hoopfer, 2016). As aggressive actions carry the risk of injury, strict regulation of aggression is needed to facilitate survival. IntroductionĪggressive behaviors are important for gaining access to resources, including food and territory, and are exhibited by both sexes in multiple species ( Anderson, 2016 Kravitz and Huber, 2003 Zwarts et al., 2012). Our work reveals important regulatory components of the neuronal circuitry that underlies female aggressive social interactions and provides tools for their manipulation. Connectomic analysis demonstrated that aIPg neurons and pC1d are interconnected and suggest that aIPg neurons may exert part of their effect by gating the flow of visual information to descending neurons. Analysis of GAL4 lines identified in an unbiased screen for increased female chasing behavior revealed the involvement of another sexually dimorphic neuron, pC1d, and implicated aIPg and pC1d neurons as core nodes regulating female aggression. Here, we identify a population of sexually dimorphic aIPg neurons in the adult Drosophila melanogaster central brain whose optogenetic activation increased, and genetic inactivation reduced, female aggression. While both sexes exhibit aggression, its neuronal underpinnings are understudied in females.
![pc1d help pc1d help](https://www.mdpi.com/electronics/electronics-08-00238/article_deploy/html/images/electronics-08-00238-ag.png)
Aggressive social interactions are used to compete for limited resources and are regulated by complex sensory cues and the organism’s internal state.