CMX-8933 is an octapeptide fragment of the goldfish brain neurotrophic factor ependymin. CMX-8933 increases the enzymatic activity of c-Jun N-terminal kinase ( JNK ), increases the phosphorylation of JNK and c-Jun proteins, and increases the cellular levels of c-Jun and c-Fos mRNA. CMX-8933 can be used to study the role of ependymin in neuroplasticity, learning, memory formation, and neural regeneration.