The development of uninucleate amoebae into multinucleate plasmodia in myxomycetes is called the amoebal-plasmodial transition (APT). During the APT in Physarum polycephalum the ability to form flagellar axonemes is lost; the astral, open mitosis is replaced by the anastral, closed mitosis; and cytoskeletal microtubules disappear. These changes are accompanied by alterations in the repertoire o...

Polypeptides preferentially labeled in the G2 phase of the synchronous nuclear replication cycle of Physarum macroplasmodia were compared in electrophoretic mobility and peptide map with the tubulins enriched from Physarum myxamoebae. One major and one minor fluorographic species match the myxamoebal alpha and beta chains, respectively. Thus, tubulins are among the proteins of Physarum selectiv...

A method was designed to purify tubulin from limited volumes of cultured cells, which can be performed in less than 4 h. The method is based on the preservation of intact microtubule arrays during cell lysis in a large volume of buffer, followed by disassembly of microtubules in a small volume of cold buffer. This allows a good enrichment in tubulin, which is then purified by one cycle of polym...

Efficient human immunodeficiency virus (HIV)-1 infection depends on multiple interactions between the viral gp41/gp120 envelope (Env) proteins and cell surface receptors. However, cytoskeleton-associated proteins that modify membrane dynamics may also regulate the formation of the HIV-mediated fusion pore and hence viral infection. Because the effects of HDAC6-tubulin deacetylase on cortical al...

CSE1L/CAS, a microtubule-associated, cellular apoptosis susceptibility protein, is highly expressed in various cancers. Microtubules are the target of paclitaxel-induced apoptosis. We studied the effects of increased or reduced CAS expression on cancer cell apoptosis induced by chemotherapeutic drugs including paclitaxel. Our results showed that CAS overexpression enhanced apoptosis induced by ...

Coated vesicles are involved in the intracellular transport of membrane proteins between a variety of membrane compartments. The coats of bovine brain coated vesicles contain at least six polypeptides in addition to an 180,000-dalton polypeptide called clathrin. In this report we show that the 54,000- and 56,000-dalton coated vesicle polypeptides are alpha- and beta-tubulin, determined by immun...

Perfluorooctane sulfonate (PFOS) is an environmental organic pollutant, the potential neurotoxicity of which is causing great concern in fish. In the present study, we examined the effects of PFOS on motor neurons, and investigated the potential toxicological mechanisms oxidative stress in zebrafish embryos. Six-hour post-fertilization (hpf) zebrafish embryos were exposed to 1.0 mg/L PFOS, then...

Changes in the amounts of tubulin, actin, and neurofilament polypeptides were found in regenerating motoneurons of grass frogs during the period of axonal elongation. Ventral roots 9 and 10 were transected unilaterally about 7 mm from the spinal cord. 35 d later, [3H]colchicine binding had decreased in the proximal stumps to approximately one-half of contralateral control values, well before th...

Previous light microscopic immunocytochemical studies using two monoclonal antibodies that recognise alpha-tubulin (YOL/34 and YL1/2) but differ in their isotypic specificity have shown that the unmyelinated parallel fiber axons in the cerebellar cortex are labeled with only one of the antibodies (YOL/34). We now show that at 10 d postnatally the parallel fibers are labeled with both antibodies...