Eyal Bengal, PhD
Associate Professor of Biochemistry
PhD, 1990 - Weizmann Institute, Israel
Transcriptional regulation of germ layer identity by MEF2 proteins during Xenopus development
The frog Xenopus is an excellent vertebrate developmental model for studying how a ball of cells becomes a patterned embryo. In Xenopus the specification of the three germ layers, ectoderm, mesoderm and endoderm, is one of the earliest developmental decisions and occurs prior to gastrulation. Early development is initiated by localized maternal mRNAs that encode signaling molecules and transcription factors. We have shown that maternally-expressed Mef2A and Mef2D transcription factors regulate germ layer specification. Before mid-blastula transition (MBT), maternal Mef2 proteins are localized to the animal half of the embryo and participate in ectoderm gene expression. After MBT, when zygotic transcription is initiated, the expression of Mef2D is extended into the marginal region of the embryo where it contributes to mesoderm specification. Research in my lab is focused on understanding why and how maternal Mef2 proteins regulate the ectoderm expression program whereas zygotic Mef2D regulates the mesoderm expression program. Currently, we are taking three approaches: bioinformatic analysis of Mef2 target genes; detailed study of Mef2 target gene-promoters; and identification of additional transcription factors and signaling pathways cooperating with Mef2. These studies will illuminate the earliest roles of MEF2 in regulating distinct transcription programs that determine germ layer fate and patterning.
Mef2 proteins are expressed in paraxial mesoderm. Histological sections (left, transverse; right, longitudinal) of stage 15 Xenopus embryos immunostained with an antibody to Mef2A and Mef2D. Nuclear staining of Mef2 is in orange.
Alter J and Bengal E. 2011. Stress-Induced C/EBP Homology Protein (CHOP) Represses MyoD Transcription to Delay Myoblast Differentiation. PLoS ONE. 6, e29498.
Keren A and Bengal E. 2010. Studying MAP Kinase pathways during early development of Xenopus laevis. Methods Mol Biol. 661, 409-420
Keren-Politansky A, Keren A, Bengal E. 2009. Neural ectoderm-secreted FGF initiates the expression of Nkx2.5 in cardiac progenitors via a p38 MAPK/CREB pathway. Dev Biol. 335, 374-384.