@article {2456, title = {Nanomechanical Properties of Tenascin-X Revealed by Single-Molecule Force Spectroscopy}, journal = {Journal of Molecular Biology}, volume = {385}, number = {4}, year = {2009}, note = {ISI Document Delivery No.: 403HJTimes Cited: 4Cited Reference Count: 35Jollymore, Ashlee Lethias, Claire Peng, Qing Cao, Yi Li, Hongbin}, month = {Jan}, pages = {1277-1286}, type = {Article}, abstract = {Tenascin-X is an extracellular matrix protein and binds a variety of molecules in extracellular matrix and on cell membrane. Tenascin-X plays important roles in regulating the structure and mechanical properties of connective tissues. Using single-molecule atomic force microscopy, we have investigated the mechanical properties of bovine tenascin-X in detail. Our results indicated that tenascin-X is an elastic protein and the fibronectin type III (FnIII) domains can unfold under a stretching force and refold to regain their mechanical stability upon the removal of the stretching force. All the 30 FnIII domains of tenascin-X show similar mechanical stability, mechanical unfolding kinetics, and contour length increment upon domain unfolding, despite their large sequence diversity. In contrast to the homogeneity in their mechanical unfolding behaviors, FnIII domains fold at different rates. Using the 10th FnIII domain of tenascin-X (TNXfn10) as a model system, we constructed a polyprotein chimera composed of alternating TNXfn10 and GB1 domains and used. atomic force microscopy to confirm that the mechanical properties of TNXfn10 are consistent with those of the FnIII domains of tenascin-X These results lay the foundation to further study the mechanical properties of individual FnIII domains and establish the relationship between point mutations and mechanical phenotypic effect on tenascin-X Moreover, our results provided the opportunity to compare the mechanical properties and design of different forms of tenascins. The comparison between tenascin-X and tenascin-C revealed interesting common as well as distinguishing features for mechanical unfolding and folding of tenascin-C and tenascin-X and will open up new avenues to investigate the mechanical. functions and architectural design of different forms of tenascins. (C) 2008 Elsevier Ltd. All rights reserved.}, keywords = {AFM, BINDING, DEFICIENCY, DOMAINS, FAMILY, FnIII domains, IDENTIFICATION, III MODULES, MECHANICAL STABILITY, mechanical unfolding, microscopy, PROTEIN, single molecule force spectroscopy, tenascin}, isbn = {0022-2836}, url = {://000263073400022}, author = {Jollymore, A. and Lethias, C. and Peng, Q. and Cao, Y. and Li, H. B.} } @article {3114, title = {IN-VIVO INHIBITION OF BETA-GLUCOSIDASE AND BETA-MANNOSIDASE ACTIVITY IN RATS BY 2-DEOXY-2-FLUORO-BETA-GLYCOSYL FLUORIDES AND RECOVERY OF ACTIVITY IN-VIVO AND IN-VITRO}, journal = {Biochemical Journal}, volume = {301}, year = {1994}, note = {ISI Document Delivery No.: PA559Times Cited: 12Cited Reference Count: 25Part 2}, month = {Jul}, pages = {343-348}, type = {Article}, abstract = {2-Deoxy-2-fluoro-beta-glucosyl and -beta-mannosyl fluorides administered to rats in a single dose(10 mg/kg) inhibited beta-glucosidase and beta-mannosidase activity respectively after 1 h in brain, spleen, liver and kidney tissues. This inhibition, presumably caused by accumulation of 2-deoxy-2-fluoroglycosyl-enzyme intermediates, indicates that intact 2-deoxy-2-fluoroglycosyl fluorides are distributed to these organs and, in the case of brain, that they cross the blood/brain barrier. beta-Glucosidase activity recovered completely or partially in brain, spleen, liver and kidney by 20-48 h. beta-Mannosidase activity partially recovered in all tissues by 48 h. beta-Galactosidase activity in brain and kidney was not significantly affected by administration of either the gluco or manno compounds at this dosage, indicating that these inhibitors are directed towards specific glycosidases. Observation of similar relatively rapid rates of beta-glycosidase re-activation in vivo and in tissue homogenates in vitro at 37 degrees C suggests that hydrolysis or transglycosylation of 2-deoxy-2-fluoroglycosyl-enzymes, not protein synthesis, are the primary mechanisms involved in the recovery of glycosidase activity inhibited by this class of compounds in vivo.}, keywords = {DEFICIENCY, ENZYME INTERMEDIATE, FORMS, GLUCOCEREBROSIDASE, GLYCOSIDASES, INACTIVATION, LIVER, MICE}, isbn = {0264-6021}, url = {://A1994PA55900006}, author = {McCarter, J. D. and Adam,Michael J. and Hartman, N. G. and Withers, S. G.} }