EvoDevo Studies in M2 Lab

Evolution of Developmental Mechanisms

Some of the very features that make C. elegans a good laboratory model also make it "exceptional"; e.g., the important and extensive roles performed by maternally expressed genes may be a consequence of a "speeded up" life cycle. Thus, using our knowledge of C. elegans development as a base, I am interested in determining to what extent the pathways that govern the identity and fates of the cells in the early embryo have been conserved among free-living nematodes. With that intent, my students and I have begun a comparative molecular genetic analysis of the early development of two species related to C. elegans: one closely related species, C. briggsae, with a developmental program that appears quite similar to C. elegans, and one distantly related species, Cephalobus sp., in which some aspects of early development appear quite radically different, yet the cell lineage remains essentially the same (e.g., the identity of one of the cells at the 4-cell stage, called "EMS", appears to be specified in a very different manner than in C. elegans, and yet in both species, EMS gives rise to the same exact tissues in the adult, i.e., gut and pharynx). By doing such a comparative study we hope to learn more about how the early stages of development can evolve independently from later stages.