DECODING THE HINDBRAIN BOUNDARIES: FROM THE GENOMIC LANDSCAPE TO THE CELLULAR FUNCTION
Speaker: Cristina Pujades, Ph.D. Group Leader of the Department of Experimental and Health Sciences, University Pompeu Fabra, PRBB, Barcelona, Spain.
Organizer: IRB Barcelona
Date: Wednesday, 27 September 2017, 15.00h
Place: Aula Felix Serratosa, Parc Científic de Barcelona, Spain
Host: Marco Milán, IRB Barcelona
The hindbrain is subdivided into seven segments called rhombomeres. At the interface between rhombomeres arises a specialized cell population displaying specific features, the rhombomere boundary cell population (BCP), which serves to distinct functions as development proceeds. First, when morphological segments arise boundary cells work as an elastic mesh, preventing cell intermingling between adjacent compartments. We have previously shown that, in zebrafish, this is due to the enrichment of actomyosin cable-like structures in their apical side, whose formation requires Eph/Ephrin signaling and downstream small GTPase effectors. During neurogenesis, hindbrain boundaries behave as a node for signaling pathways instructing the differentiation and organization of neurons in the neighboring rhombomeres. Later, hindbrain boundaries provide proliferating progenitors and differentiating neurons to the hindbrain. Therefore, a fundamental question is how these cells coordinately unfold their distinct functional properties over the entire program of hindbrain morphogenesis. I will discuss how we have identified the regulatory modules underlying the specific activation of morphogenetic genes in the boundary domain, identifying hindbrain boundaries-specific cis-regulatory elements. In addition, we have explored the contribution of the BCP to hindbrain cell diversity by cell lineage studies and addressed the potential role of Yap/Taz-TEAD activity in maintaining neuronal progenitor capacity within these territories.
Cell and Developmental Biology Programme Seminar