Functional KCC2 expression is regulated by REST: immunocytochemistry. Primary cortical neurons were cotransfected with copepod-GFP and FL-REST, dn-REST, or vector control, followed by immunostaining at DIV7. KCC2 immunoreactivity appears in red (left column), copepod-GFP in green (middle column), and merged (right column). Inset is a magnified view of KCC2 immunoreactive neurons, showing an increase of labeling intensity toward the edge of the soma, indicating transmembrane staining.