Is there a brain in the gonad??!?

Passerine birds tune their reproductive systems so that young hatch in times of optimal resources. For temperate species, resource availability is not constant year round, thus they only breed at one time of the year. House sparrows and starlings rely principally on unchanging yearly photoperiods for timing. However, other cues such as temperature, presence of conspecifics, rainfall, and food availability can alter the timing of their breeding schedules. Traditionally, an organism’s integration of environmental cues happens at the level of the brain. It is thus appropriate that start and stop signals for the reproductive axis, in the form of gonadotropin releasing hormone (GnRH) and gonadotropin inhibitory hormone (GnIH), occur in the diencephalon. However, the regression and dramatic recrudescence of the testis and follicular development in the ovary that precede breeding may require localized fine tuning.

I am currently working on characterizing a “neuropeptide” system within the gonads of these birds. Based on prior work of Dr. Bentley, Dr. Tsutsui, and Dr. Ubuka, my research focuses on identifying locations of synthesis and functional significance of GnRH, GnIH and their respective receptors within the gonads. In the future, I also hope to identify this system in frogs, lizards, turtles and sheep.

Nicolette McGuire *Ph.D. Student* Department of Integrative Biology University of California, Berkeley
Contact: nicolette@berkeley.edu
C.V.
Research Interests:
Is there a brain in the gonad??!? Passerine birds tune their reproductive systems so that young hatch in times of optimal resources. For temperate species, resource availability is not constant year round, thus they only breed at one time of the year. House sparrows and starlings rely principally on unchanging yearly photoperiods for timing. However, other cues such as temperature, presence of conspecifics, rainfall, and food availability can alter the timing of their breeding schedules. Traditionally, an organism’s integration of environmental cues happens at the level of the brain. It is thus appropriate that start and stop signals for the reproductive axis, in the form of gonadotropin releasing hormone (GnRH) and gonadotropin inhibitory hormone (GnIH), occur in the diencephalon. However, the regression and dramatic recrudescence of the testis and follicular development in the ovary that precede breeding may require localized fine tuning. I am currently working on characterizing a “neuropeptide” system within the gonads of these birds. Based on prior work of Dr. Bentley, Dr. Tsutsui, and Dr. Ubuka, my research focuses on identifying locations of synthesis and functional significance of GnRH, GnIH and their respective receptors within the gonads. In the future, I also hope to identify this system in frogs, lizards, turtles and sheep.