Monoclonal antibodies specific for either the tyrosinated (Tyr) or the detyrosinated (Glu) form of alpha-tubulin were elicited with synthetic peptides spanning the carboxy-terminal sequences of the two forms. While almost all microtubules (MTs) are usually of the Tyr-tubulin type (Tyr-rich MTs) some MTs containing noticeable amounts of Glu-tubulin (Glu-rich MTs) were found in many but not all c...

The Notch signal pathway plays important roles in proliferation, apoptosis, and differentiation. Abnormalities in Notch signaling are linked to many human diseases. After ligand binding, Notch signaling is activated through the cleavage of Notch receptors to release and translocate the Notch intracellular domain into the nucleus. The Notch1 receptor intracellular domain (N1IC), the activated fo...

We have developed a straightforward, two-step procedure to isolate highly purified yeast tubulin that reproducibly assembles into microtubules. The starting extracts are obtained from cells genetically engineered to overproduce both the alpha and beta subunits of tubulin, under control of the galactose promoter, to approximately 10-times wild-type levels. The first step of purification is carri...

The antitumor drug paclitaxel stabilizes microtubules and reduces their dynamicity, promoting mitotic arrest and eventually apoptosis. Upon assembly of the alpha/beta-tubulin heterodimer, GTP becomes bound to both the alpha and beta-tubulin monomers. During microtubule assembly, the GTP bound to beta-tubulin is hydrolyzed to GDP, eventually reaching steady-state equilibrium between free tubulin...

Anisotropic expansion of plant cells requires organized arrays of cortical microtubules. Mutations in microtubule-associated proteins and a particular mutation in alpha-tubulins were reported to cause abnormal microtubule arrays and result in helical growth in Arabidopsis thaliana. However, the way in which these mutations affect the organization of microtubules remains unknown. We here identif...

The C-terminus of alpha-tubulin undergoes a reversible posttranslational tyrosination/detyrosination. The distributions of the tyrosinated (Tyr) and nontyrosinated (Glu) species during mitosis of cultured cells have been investigated by immunofluorescence using antibodies directed against the C-terminus of either Tyr or Glu tubulin. The distribution of Tyr tubulin differed from that of Glu tubu...

Tubulin, the major constituent protein of microtubules, is a heterodimer of alpha and beta subunits. Both alpha and beta exist in multiple isotypic forms. It is not clear if different isotypes perform different functions. In order to approach this question, we have made a monoclonal antibody specific for the beta III isotype of tubulin. This particular isotype is neuron-specific and appears to ...

Polyclonal (PAT) and monoclonal (AXO 49) antibodies against Paramecium axonemal tubulin were used as probes to reveal tubulin heterogeneity. The location, the nature and the subcellular distribution of the epitopes recognized by these antibodies were, respectively, determined by means of: (i) immunoblotting on peptide maps of Paramecium, sea urchin and quail axonemal tubulins; (ii) immunoblotti...

The eukaryotic cytoskeletal protein tubulin is a heterodimer of two subunits, alpha and beta, and is a building block unit of microtubules. In a previous communication we demonstrated that tubulin possesses chaperone-like activities by preventing the stress-induced aggregation of various proteins (Guha, S., Manna, T. K., Das, K. P., and Bhattacharyya, B. (1998) J. Biol. Chem. 273, 30077-30080)....

Advanced stage neuroblastoma has a poor clinical outcome and microtubule-destabilizing agents, such as the Vinca alkaloids, are an important component in the treatment of this childhood cancer. Vinca alkaloids bind to beta-tubulin on the alpha/beta-tubulin heterodimer and disrupt microtubule dynamics, leading to cell death. To date, studies examining the contribution of microtubules and associa...