Ruth Johnson, assistant professor of biology, assistant professor of integrative sciences, is the co-author of a new paper titled “The adaptor protein Cindr regulates JNK activity to maintain epithelial sheet integrity” published in the journal Developmental Biology on Jan. 7. The paper was co-authored by Hannah Yasin ’15, Samuel van Rensburg MA ’15, and Christina Feiler, an exchange masters student who worked in Johnson’s lab during 2012-13. The publication represents Yasin’s honors thesis, and van Rensburg’s and Feiler’s masters theses.
According to the abstract:
Epithelia are essential barrier tissues that must be appropriately maintained for their correct function. To achieve this a plethora of protein interactions regulate epithelial cell number, structure and adhesion, and differentiation. Here we show that Cindr (the Drosophila Cin85 and Cd2ap ortholog) is required to maintain epithelial integrity. Reducing Cindr triggered cell delamination and movement. Most delaminating cells died. These behaviors were consistent with JNK activation previously associated with loss of epithelial integrity in response to ectopic oncogene activity. We confirmed a novel interaction between Cindr and Drosophila JNK (dJNK), which when perturbed caused inappropriate JNK signaling. Genetically reducing JNK signaling activity suppressed the effects of reducing Cindr. Furthermore, ectopic JNK signaling phenocopied loss of Cindr and was partially rescued by concomitant cindr over-expression. Thus, correct Cindr-dJNK stoichiometry is essential to maintain epithelial integrity and disturbing this balance may contribute to the pathogenesis of disease states, including cancer.