Lithium-sensitive production of inositol phosphates during amphibian embryonic mesoderm induction

See allHide authors and affiliations

Science  10 Apr 1992:
Vol. 256, Issue 5054, pp. 243-245
DOI: 10.1126/science.1314424


Mesoderm induction and body axis determination in frog (Xenopus) embryos are thought to involve growth factor-mediated cell-cell signaling, but the signal transduction pathways are unknown. Li+, which inhibits the polyphosphoinositide (PI) cycle signal transduction pathway in many cells, also disrupts axis determination and mesoderm induction. Amounts of the PI cycle-derived second messenger, inositol 1,4,5-trisphosphate, increased during mesoderm induction in normal embryos; addition of Li+ inhibited the embryonic inositol monophosphatase and reversed this increase. Embryonic PI cycle activity thus shows characteristics that indicate it may function in mesoderm induction and axis determination.