Mechanisms of cytoskeletal injury by heavy metals.
Department of Microbiology, School of Medicine, Boston University, Boston, Massachusetts 1989 Jun; :1-4
The major aim of this study was to determine whether metallothionein (MT) disassembly and inhibition of assembly caused by cadmium (7440439), mercury (7439976), and lead (7439921) in cultured 3T3 cells was due to binding to tubulin sulfhydryl groups or binding to and activation of CaM. Methylmercury was used as a model for adverse effects to MT due to tubulin sulfhydryl binding in the extracted cytoskeleton model system and during the polymerization of purified MT proteins in-vitro. The results indicated that, like calcium, the inhibitory effect of cadmium on the polymerization of purified MT proteins containing tubulin and microtubule associated proteins was enhanced by exogenously added CaM, suggesting that microtubule associated proteins were involved in mediating the sensitivity of MT to cadmium activated CaM. The findings that cadmium, like calcium, can support the binding of CaM to tubulin and MAPs in Western blots of purified MT proteins support the proposal that MAPs are important in the increased sensitivity of MT to cadmium activated CaM. The stimulation by cadmium or calcium/CaM dependent protein-kinase-II, resulting in MAP phosphorylation and MT disassembly and inhibition of assembly was not investigated.
NIOSH-Grant; Grants-other; Metallic-poisoning; Heavy-metal-poisoning; Protein-chemistry; Protein-synthesis; Mercury-poisoning; Lead-poisoning
Microbiology Boston University 80 East Concord Street Boston, Mass 02118
7440-43-9; 7439-97-6; 7439-92-1
Final Grant Report
NTIS Accession No.
Other Occupational Concerns; Grants-other
Department of Microbiology, School of Medicine, Boston University, Boston, Massachusetts
Boston University, Boston, Massachusetts