Meeting Abstract
Acoustic communication, including vocalization, occurs in many animal species. Vocal animals produce either unlearned/innate sounds or a combination of both unlearned and learned sounds. Research into the molecular basis of vocalization has focused primarily on the production of learned sounds and has identified a suite of genes including foxp2, foxp1, and cntnap2 as regulators of this behavior. Little is currently known about how this suite of genes is expressed in highly vocal species that only produce unlearned vocalizations. Hyla cinerea (green treefrog) is an organism that produces unlearned vocalizations. Additionally, only males produce vocalizations in this species. We determined if this network of genes (foxp2, foxp1, and cntnap2) is expressed in both a regionally specific and/or sex-specific manner. Male and female brains were trisected and RNA was extracted using TRIzol (Invitrogen). Transcription levels of foxp2, foxp1, and cntnap2 were then measured in each brain region of each sex using quantitative PCR. Analysis revealed a regional difference in both fox genes with foxp2 exhibiting highest expression in the midbrain when compared to either the forebrain or the hindbrain (p<0.00001). foxp1 expression is significantly lower in the hindbrain than in either the midbrain (p=0.0002) or the forebrain (p=0.035). cntnap2 did not exhibit a regional difference in expression. None of these genes exhibit a difference in expression based on sex. These data suggest that this suite of genes is not specifically tied to sex differences in vocal production, or that potential sex differences exist in specific brain nuclei that are lost in gross regional characterization.
