2013. Rutgers University. M.S.
The nervous system is comprised of unique neuronal types that are organized into complex networks during development. Deciphering the genetic instructions that underlie neuronal diversity is a major goal of developmental neurobiology. Studies in both vertebrates and invertebrates revealed that space and time are two axes of information used by neural progenitors to determine where and when specific neurons should be produced. Major advances have been made in dissecting the molecular mechanisms of spatial patterning, yet the mechanisms of temporal patterning are just beginning to be understood.A unique model to study temporal patterning is the Drosophila mushroom bodies (MBs), two paired ganglia located in the central brain that are required for olfactory learning and memory. Each MB consists of ~2000 neurons of only seven neuronal types that are born sequentially from four identical neuroblasts: first, two types of γ neurons are born, followed by two types of α’β’ and finally three types of αβ neurons. In contrast to other Drosophila neuroblast lineages, in which many more temporal windows (up to 80) last for a short period of time and the switch from one temporal window to the next is intrinsically regulated, the seven MB temporal windows range between ~10-60 cell divisions and require extrinsic signaling for their transition. Given that MB neuronal types are born sequentially and exhibit unique morphological, molecular and functional characteristics, we hypothesize that each MB temporal window is defined by the expression of temporal transcription factors (tTFs) in MB neuroblasts during development. We posit that MB tTFs are the upstream regulators of genes that specify and maintain the identity of mature MB neurons. We will study the identity of both MB neuroblasts as they progress through development and of mature MB neurons in the adult.
NIH T32 Training Grant – Current