I am broadly interested in gene regulation and cellular processes that are instructive for embryonic development. As a graduate student, I made several discoveries relating to the specification, patterning, and morphogenesis of embryonic neural and cardiac progenitors in the tunicate Ciona intestinalis. Recognizing the largely untapped potential of Ciona and other tunicates as model organisms for developmental genetics, I have continued my postdoctoral research working on these invertebrate chordates. During my post-doc, I have developed additional tools for the study of gene function in Ciona and established myself as a young leader of the tunicate research community. The K99/R00 award will allow me to complete my formal training and begin my transition to a role as an independent investigator, at the helm of a research group studying cellular morphogenesis in tunicate embryonic development. For this project, I propose to study gene function in regulation of migration and polarization of two distinct cell types in the Ciona embryo, the Trunk Ventral Cells (TVCs) and the Bipolar Tail Neurons (BTNs). In the K99 mentored phase, I will first investigate gene function by CRISPR/Cas9- mediated mutagenesis in the TVCs, which undergo stereotyped directed migration and polarity orientation. I will then profile the transcriptome of te BTNs, identifying Candidate genes that may regulate stereotyped directed migration and orientation of polarity. The completion of these aims will prepare me for pursuing my third aim, to be performed in the R00 mentored phase, of testing the requirement for those Candidate genes in the BTNs, allowing for direct comparisons between the molecular control of migration and polarity in different cell types in different niches of the same embryo. The mentored phase fits the research interests of both my mentor, Dr. Christiaen, and I. We both aim to understand how cell behavior is regulated, and how deficiencies in this regulatory control may result in developmental syndromes and human disease. Where I hope to distinguish myself from my mentor during the independent phase and beyond is in my particular interest in neural development and neuronal differentiation, in contrast to Dr. Christiaen's focus on cardiac development. The K99 award will allow me to complete my postdoctoral training, by learning and meaningfully applying FACS, RNA-seq, and automated imaging techniques. The K99 will also enable me to generate preliminary data that I can take with me as the foundation for an independent research program.
Human embryonic and post-natal development depend greatly on the shaping and movements of individual cells, which in turn are determined through both intrinsic properties of the cell and by extrinsic cues provided by surrounding cells. Developmental syndromes occur when there is a breakdown in the regulation of these cell behaviors in specific cells of complex tissues and organs forming in an embryo or child. I will use the small, transparent embryos of Ciona, one of the invertebrates most closely related to humans, to better understand cell behaviors as they happen in the developing heart and nervous system, and to identify which genes are activated to regulate such behaviors.
| Gandhi, Shashank; Razy-Krajka, Florian; Christiaen, Lionel et al. (2018) CRISPR Knockouts in Ciona Embryos. Adv Exp Med Biol 1029:141-152 |
| Racioppi, Claudia; Valoroso, Maria Carmen; Coppola, Ugo et al. (2017) Evolutionary loss of melanogenesis in the tunicate Molgula occulta. Evodevo 8:11 |
| Gandhi, Shashank; Haeussler, Maximilian; Razy-Krajka, Florian et al. (2017) Evaluation and rational design of guide RNAs for efficient CRISPR/Cas9-mediated mutagenesis in Ciona. Dev Biol 425:8-20 |
