Poster abstracts
Poster number 64 submitted by Allison Webb
EGL-38/PAX protein coordination of cell fates in the Caenorhabditis elegans egg-laying system
Allison Webb (OSBP), Ryan Johnson (OSU Molecular Genetics ), Helen Chamberlin (OSU Molecular Genetics)
Abstract:
The Paired-box family of transcription factors is an essential regulator of coordinated development throughout Metazoans, necessary for cell growth, differentiation, and specification. We seek to understand how PAX functions in unrelated but neighboring cells to synchronize cell fates by utilizing the PAX2/5/8 Caenorhabditis elegans ortholog EGL-38. EGL-38 is required in both epithelial and mesodermal cells of the egg-laying system for creation of the vulval-uterine connection. In the epithelial vulF cell, EGL-38 is known to be required for expression of lin-3/egf, which initiates the EGF pathway to specify the uv1 cell identity. In the mesodermal uv1 cell, we have discovered that egl-38 uv1 expression is dependent on EGL-38 in vulF as well as on the EGF pathway signal. Conversely, we have shown that EGL-38 activation of the uv1 neuropeptide nlp-2 is EGF pathway independent, and are currently investigating EGL-38 activation of the related nlp-7 in uv1. We are also examining the role of LIN-1, a potential EGL-38 co-factor, for involvement with lin-3/egf, nlp-2, and nlp-7 expression; a co-factor would provide a mechanism of restricting EGL-38 activities to specific cells. This dichotomous EGL-38 activity- triggering a signaling pathway in one cell type and responding to that signal in a different cell type- is an unusual behavioral motif that may be found in other Pax proteins to explain how they coordinate the fates of disparate cells.
Keywords: Pax proteins, Signaling pathway, Transcription