Ascidian development and cytoplasmic reorganizations: dissecting the mechanisms that pattern developmental determinants and shape embryonic development

What makes a head different from a tail?

In many animals, the asymmetries that underlieThe asymmetric distribution of cytoplasmic domains and RNAs is critical for asymmetric cell division and fate determination.

Therefore, unraveling the mechanisms that drive the asymmetric distribution of the cytoplasm is essential for understanding animal development.

Once fertilized, ascidian eggs undergo a massive cytoplasmic reorganization that precisely localizes developmental determinants (proteins and RNAs) to establish the anterior-posterior body axis.

Following this reorganization, an invariant cleavage pattern predictably segregates determinants asymmetrically into blastomeres, conferring differential cell fates. Thus, polarity in the ascidian egg determines the body plan of the whole animal.

Despite its vital role in establishing embryonic patterning, remarkably little is known about the mechanisms that orchestrate cytoplasmic reorganization and the distribution of developmental factors.

In this project, I will use develop a multidisciplinary approach, combining high-resolution microscopy and force and cell shape manipulations, proximity biotinylation, proteomics, and transcriptomics to address the following fundamental questions: 1) What mechanisms regulate cytoplasmic reorganization and anterior-posterior polarity in the ascidian egg? 2) How is cytoplasmic reorganization translated into the precise positioning of developmental determinants?

This study will shed light on the processes that define the anterior-posterior body axis and pattern of development in ascidians and deepen our understanding of how embryogenesis is conserved and has evolved among chordates.

Throughout this project, I will not only acquire new technical skills but also build upon my project management, communication, and leadership skills towards my goal of becoming an independent researcher investigating how the cytoskeleton establishes cellular morphology and organization to inform cell function.