We previously reported that, following inhibition of cytochrome c oxidase activity by endogenous nitric oxide (1), astrocytes can maintain energy homeostasis and survival by reactivating the glycolytic pathway; however, this metabolic and survival response was not invoked by neurons (2). Recently, we elucidated the signalling mechanism responsible for those metabolic effects found in astrocytes, and identified that the AMP-activated protein kinase (AMPK) and 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (Pfkfb or Pfk2) pathway played an essential role (3). Pfkfb catalyzes the formation and degradation of fructose-2,6-bisphosphate, i.e. the most potent positive alosteric effector of 6-phosphofructo-1-kinase (Pfk1) –a master regulator of the glycolytic pathway (4). Here, we sought to investigate whether the control of glycolysis and survival of cortical neurons in primary culture would lie on the regulation of Pfkfb. Western blot analyses, using a specific antibody that we raised against the brain Pfkfb isoform (Pfkfb3) revealed that the Pfkfb3 protein was profusely expressed in rat cortical astrocytes in primary culture. In contrast, the Pfkfb protein was undetectable in terminally differentiated rat cortical neurons in primary culture. Interestingly, we found that the Pfkfb3 protein was expressed in undifferentiated neuronal precursors, but it progressively disappeared along with the differentiation process. In contrast, Pfkfb3 mRNA, as assessed by Northern blotting, was found to be present at any differentiation stages. Furthermore, inhibition of the proteasome activity using MG132 rapidly induced the accumulation of the Pfkfb3 protein in fully differentiated, post-mitotic neurons. Finally, over-expression of Pfkfb3 full-length cDNA altered neuronal survival during terminal differentiation. Together, these results strongly suggest that neuronal glycolysis and survival can be controlled by the stability of Pfkfb3 through the ubiquitin-proteasome pathway. This may have implications for our understanding of the mechanisms of neurodegeneration by oxidative and nitrosative stress.