Glyoxal-based fixation of Drosophila embryos for immunofluorescence staining and RNA in situ hybridization.

The dialdehyde glyoxal is an alternative chemical fixative that cross-links tissues faster than formaldehyde, retains higher antigenicity, and is less hazardous than either formaldehyde or glutaraldehyde. Here we present a glyoxal-based fixation protocol for use with Drosophila embryos. We describe steps to prepare acid-free glyoxal, fix embryos, and then stain with antibodies for immunofluorescence (IF).

Phosphorylation hotspot in the C-terminal domain of occludin regulates the dynamics of epithelial junctional complexes.

The apical junctional complex (AJC), which includes tight junctions (TJs) and adherens junctions (AJs), determines the epithelial polarity, cell-cell adhesion and permeability barrier. An intriguing characteristic of a TJ is the dynamic nature of its multiprotein complex. Occludin is the most mobile TJ protein, but its significance in TJ dynamics is poorly understood.