title: Using a kinase/phosphatase switch to regulate a supramolecular hydrogel and forming the supramolecular hydrogel in vivo.
abstract: We have designed and synthesized a new hydrogelator Nap-FFGEY (1), which forms a supramolecular hydrogel. A kinase/phosphatase switch is used to control the phosphorylation and dephosphorylation of the hydrogelator and to regulate the formation of supramolecular hydrogels. Adding a kinase to the hydrogel induces a gel-sol phase transition in the presence of adenosine triphosphates (ATP) because the tyrosine residue is converted into tyrosine phosphate by the kinase to give a more hydrophilic molecule of Nap-FFGEY-P(O)(OH)(2) (2); treating the resulting solution with a phosphatase transforms 2 back to 1 and restores the hydrogel. Electron micrographs of the hydrogels indicate that 1 self-assembles into nanofibers. Subcutaneous injection of 2 in mice shows that 80.5 +/- 1.2% of 2 turns into 1 and results in the formation of the supramolecular hydrogel of 1 in vivo. This simple biomimetic approach for regulating the states of supramolecular hydrogels promises a new way to design and construct biomaterials.
authors.affiliation: Department of Chemistry and Bioengineering Program, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
authors.forename: Zhimou
authors.initials: Z
authors.lastname: Yang
authors.forename: Gaolin
authors.initials: G
authors.lastname: Liang
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.forename: Bing
authors.initials: B
authors.lastname: Xu
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D002942:Circular Dichroism; D006367:HeLa Cells; D006801:Humans; D020100:Hydrogels / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D008958:Models, Molecular; D010744:Phosphoric Monoester Hydrolases / Q000737:chemistry* / Q000378:metabolism; D010766:Phosphorylation; D010770:Phosphotransferases / Q000737:chemistry* / Q000378:metabolism; D012212:Rheology; D014443:Tyrosine / Q000737:chemistry / Q000378:metabolism
chemical_list: D020100:Hydrogels; D014443:Tyrosine; D000255:Adenosine Triphosphate; D010770:Phosphotransferases; D010744:Phosphoric Monoester Hydrolases