This application addresses broad Challenge Area (01) Behavior, Behavioral Change, and Prevention and specific Challenge Topic, 01-GM-102: Model organisms for social behavior studies. Songbirds offer unique untapped advantages for integrative analyses of the genetic, biochemical, physiological, and environmental components of social behavior. Songbirds have complex nervous systems and are proven models for health-related brain research. They form complex and diverse social groups, and populate most ecosystems world-wide. The genome of one songbird, the zebra finch, has now been sequenced by the NIH. There remain two main barriers to the use of songbirds to investigate mechanisms of social behavior. The overall goal of this proposal is to break down these barriers and open a path for future research using songbirds as models for social behavior. The zebra finch is a gregarious colonial species that has been domesticated and is common in labs (and homes) around the world. Wild zebra finches are difficult to study in their native habitat (Australia) but the domesticated zebra finch has proven to be an exceptional experimental model. There have been careful descriptions of sociality in wild zebra finches, and focused lab investigations on mate choice and song learning - yet a formal scientific profile of the social behavior of the domesticated zebra finch does not exist. Moreover, how individuals vary in their social behavior is unexamined. To leverage the genomic investment in the zebra, these knowledge gaps need to be filled.
Aim 1 will address this first barrier by constructing an """"""""ethogram"""""""" to describe the social behavior in a zebra finch aviary across multiple generations. Additional experiments will evaluate how stable individual variation (""""""""personality"""""""") affects the response to an acute social challenge (song playback). Results from these studies will inform Year 2 experiments comparing socially-driven brain gene expression in different contexts and individuals.
Aim 2 addresses a complementary challenge: songbird diversity offers rich opportunities to compare related species that differ in social behavior and to study accessible species in their native environments, but only zebra finch gene sequence information is currently available. To overcome this barrier and enable the application of genomic tools to comparative analyses of social behavior, brain transcriptomes will be assembled for three key species: the violet-eared waxbill - a close relative of the zebra finch;and the song and white-crowned sparrows - major foci for North American behavioral ecology. These songbirds, in combination with the zebra finch, represent pairs of related species that display striking contrasts in social behavior (levels of social aggression) and therefore have tremendous potential for development as avian models for genomic studies of social behavior.
Many of the most important challenges for public health require a better understanding of how social factors impinge on the biology of the individual, and how variations in individuals influence social organization and function. Probing these links requires appropriate model organisms.
This research aims to exploit natural advantages of songbirds as models for social behavior, leveraging recent progress with songbird neurobiology and genomics.
| Balakrishnan, Christopher N; Chapus, Charles; Brewer, Michael S et al. (2013) Brain transcriptome of the violet-eared waxbill Uraeginthus granatina and recent evolution in the songbird genome. Open Biol 3:130063 |
| Balakrishnan, Christopher N; Lin, Ya-Chi; London, Sarah E et al. (2012) RNA-seq transcriptome analysis of male and female zebra finch cell lines. Genomics 100:363-9 |
