Maureen Cetera

The Cetera lab studies how cells communicate directional information across tissues during embryogenesis. When cells are unable to sense direction, severe developmental defects occur such as open neural tube defects, congenital heart defects, shortened body axes, and loss of hearing. The Planar Cell Polarity (PCP) pathway allows cells to orient themselves in the same direction across a tissue where they can produce polarized structures or contribute to polarized motion in order to shape the embryo. Although we understand how PCP is coordinated across short distances, it is not known how it is coordinated across millions of cells. The main hypothesis in the field is that a directional cue functions upstream of the PCP pathway to orient its organization with respect to a tissue axis. However, we still do not know the identity of the directional cues or how they function. A major challenge to identifying these factors is that they are also required for tissue growth and development. To avoid this problem, the researchers use vertebrate model systems where genes have duplicated and evolved to take on specialized functions. Specifically, they use the vertebrate skin, where PCP has been shown to direct the orientation of fur and feathers. Spontaneous mutants have developed in birds, dogs, guinea pigs, and mice that cause reversal of fur or feather orientation, suggesting the gene that is altered is responsible for patterning PCP in the skin but does not alter the viability of the animal. By uncovering the molecular nature of these mutations we can gain insight into how PCP is organized during embryogenesis.