pen/lgl2 mutant epidermal cells differentially express EMT regulators.
Graphical representation of expression data of some of the relevant genes obtained by microarray (A) and quantitative RT-PCR (B). RNA In situ hybridization analysis in wild-type (C, E, G, I, K) and pen/lgl2 mutant larvae (D, F, H, J, L) at 5dpf. Gene expression data obtained by microarray analysis reveals strong transcriptional activation of EMT associated matrix metalloproteinases like mmp9 and mmp13, cell-cycle related genes like proto-oncogene jun-b and histone 2b, whereas expression of cytokeratins like krt5 or cyt1 is decreased. Interestingly, tight junction proteins cldn7, cldne as well as adherens junction component E-cad and serum- and glucocorticoid-induced kinase-1 (sgk1) were also up-regulated in pen/lgl2 mutant. RT-PCR analysis (B) revealed that E-cad expression is indeed significantly up-regulated in mutant larvae with marginal decrease in snail expression levels. In situ hybridization analysis (C–L) reveals that the relevant genes are differentially expressed in the epidermis. Note that cldn7 is highly up-regulated in the cellular clumps in the finfold (arrows in H). ** = P<0.005