title: Rbl2p, a yeast protein that binds to beta-tubulin and participates in microtubule function in vivo.
abstract: Genetic configurations resulting in high ratios of beta-tubulin to alpha-tubulin are toxic in S. cerevisiae, causing microtubule disassembly and cell death. We identified three non-tubulin yeast genes that, when overexpressed, rescue cells from excess beta-tubulin. One, RBL2, rescues beta-tubulin lethality as efficiently as does alpha-tubulin. Rbl2p binds to beta-tubulin in vivo. Deficiencies or excesses of either Rbl2p or alpha-tubulin affect microtubule-dependent functions in a parallel fashion. Rbl2p has functional homology with murine cofactor A, a protein important for in vitro assays of beta-tubulin folding. The results suggest that Rbl2p participates in microtubule morphogenesis but not in the assembled polymer.
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge 02139, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Archer
authors.forename: L R
authors.initials: LR
authors.lastname: Vega
authors.forename: F
authors.initials: F
authors.lastname: Solomon
mesh_terms: D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000302:isolation & purification* / Q000502:physiology; D008870:Microtubules / Q000502:physiology*; D008969:Molecular Sequence Data; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D016415:Sequence Alignment; D014404:Tubulin / Q000502:physiology*
chemical_list: D005656:Fungal Proteins; D014404:Tubulin