title: Pfkfb (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase) isoforms display a tissue-specific and dynamic expression during Xenopus laevis development.
abstract: Pfkfb (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase) enzymes are bi-functional enzymes encoded by four different genes (pfkfb1, pfkfb2, pfkfb3, pfkfb4) in vertebrates. They are involved in the regulation of glycolysis: they catalyze the synthesis and the degradation of F-2,6-BP (fructose-2,6-bisphosphate), the most potent allosteric activator of phosphofructokinase 1 (Pfk1), a key glycolytic enzyme. By producing F-2,6-BP, Pfkfb enzymes allow glycolysis to proceed, while by degrading F-2,6-BP they block glycolysis. As major regulators of glycolysis, Pfkfb enzymes are involved in cancer: tumor cells have a higher glycolytic rate compared to normal cells, even in the presence of adequate oxygen levels (Warburg effect) and several cancer cell lines express elevated levels of Pfkfb enzymes. Glycolysis is also important for energy and metabolite production in proliferating cells. In embryos, however, the role of glycolysis and the expression of glycolysis regulators remain to be explored. Here, we provide a phylogenetic analysis of Pfkfb enzymes in vertebrates, and we detail the expression pattern of pfk1, pfkfb1, pfkfb2, pfkfb3, and pfkfb4 genes in Xenopus laevis embryos. We show that pfkfb transcripts expression is overlapping at blastula and gastrula stages and that from neurulation to tadpole stages, they display tissue-specific, complementary and dynamic expression patterns.
authors.affiliation: Institut Curie, Research Division, Centre Universitaire, Orsay F-91 405, France.
authors.forename: Caterina
authors.initials: C
authors.lastname: Pegoraro
authors.forename: Frederique
authors.initials: F
authors.lastname: Maczkowiak
authors.forename: Anne H
authors.initials: AH
authors.lastname: Monsoro-Burq
mesh_terms: D000818:Animals; D015870:Gene Expression; D006019:Glycolysis / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics* / Q000378:metabolism; D025481:Phosphofructokinase-2 / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D016415:Sequence Alignment; D062211:Spatio-Temporal Analysis; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D025481:Phosphofructokinase-2