TY - JOUR
T1 - γ-tubulin in Chlamydomonas
T2 - Characterization of the gene and localization of the gene product in cells
AU - Silflow, C. D.
AU - Liu, B.
AU - LaVoie, M.
AU - Richardson, E. A.
AU - Palevitz, B. A.
PY - 1999
Y1 - 1999
N2 - In addition to their role in nucleating the assembly of axonemal microtubules, basal bodies often are associated with a microtubule organizing center (MTOC) for cytoplasmic microtubules. In an effort to define molecular components of the basal body apparatus in Chamydomonas reinhardtii, genomic and cDNA clones encoding γ-tubulin were isolated and sequenced. The gene, present in a single copy in the Chlamydomonas genome, encodes a protein with a predicted molecular mass of 52,161 D and 73% and 65% conservation with γ- tubulin from higher plants and humans, respectively. To examine the distribution of γ-tubulin in cells, a polyclonal antibody was raised against two peptides contained within the protein. Immunoblots of Chlamydomonas proteins show a major cross-reaction with a protein of Mr 53,000. In Chlamydomonas cells, the antibody stains the basal body apparatus as two or four spots at the base of the flagella and proximal to the microtubule rootlets. During cell division, two groups of fluorescent dots separate and localize to opposite ends of the mitotic apparatus. They then migrate during cleavage to positions known to be occupied by basal bodies. Changes in γ- tubulin localization during the cell cycle are consistent with a role for this protein in the nucleation of microtubules of both the interphase cytoplasmic array and the mitotic spindle. Immunogold labeling of cell sections showed that γ-tubulin is closely associated with the basal bodies. The flagellar transition region was also labeled, possibly indicating a role for γ-tubulin in assembly of the central pair microtubules of the axoneme.
AB - In addition to their role in nucleating the assembly of axonemal microtubules, basal bodies often are associated with a microtubule organizing center (MTOC) for cytoplasmic microtubules. In an effort to define molecular components of the basal body apparatus in Chamydomonas reinhardtii, genomic and cDNA clones encoding γ-tubulin were isolated and sequenced. The gene, present in a single copy in the Chlamydomonas genome, encodes a protein with a predicted molecular mass of 52,161 D and 73% and 65% conservation with γ- tubulin from higher plants and humans, respectively. To examine the distribution of γ-tubulin in cells, a polyclonal antibody was raised against two peptides contained within the protein. Immunoblots of Chlamydomonas proteins show a major cross-reaction with a protein of Mr 53,000. In Chlamydomonas cells, the antibody stains the basal body apparatus as two or four spots at the base of the flagella and proximal to the microtubule rootlets. During cell division, two groups of fluorescent dots separate and localize to opposite ends of the mitotic apparatus. They then migrate during cleavage to positions known to be occupied by basal bodies. Changes in γ- tubulin localization during the cell cycle are consistent with a role for this protein in the nucleation of microtubules of both the interphase cytoplasmic array and the mitotic spindle. Immunogold labeling of cell sections showed that γ-tubulin is closely associated with the basal bodies. The flagellar transition region was also labeled, possibly indicating a role for γ-tubulin in assembly of the central pair microtubules of the axoneme.
KW - Basal body
KW - Chlamydomonas
KW - Microtubule organizing center
KW - γ-tubulin
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U2 - 10.1002/(SICI)1097-0169(1999)42:4<285::AID-CM3>3.0.CO;2-Z
DO - 10.1002/(SICI)1097-0169(1999)42:4<285::AID-CM3>3.0.CO;2-Z
M3 - Article
C2 - 10223635
AN - SCOPUS:0032948132
SN - 0886-1544
VL - 42
SP - 285
EP - 297
JO - Cell Motility and the Cytoskeleton
JF - Cell Motility and the Cytoskeleton
IS - 4
ER -