title: Changes in the Accumulation of [alpha]- and [beta]-Tubulin Isotypes during Cotton Fiber Development.
abstract: The expression of [alpha]- and [beta]-tubulin proteins in developing fibers and several other tissues of cotton (Gossypium hirsutum, cv Texas Marker 1) have been analyzed by immunoblots of one- and two-dimensional gels utilizing anti-tubulin antibodies as probes. As a percentage of total protein, fibers had greater amounts of tubulin than did hypocotyls, roots, leaves, or cotyledons. Both [alpha]- and [beta]-tubulin, having apparent molecular masses of approximately 50 kD and isoelectric points between pH 5 and pH 6, were resolved on a single two-dimensional gel. Under the conditions used, [alpha]-tubulin was less acidic in the isoelectric focusing dimension and migrated slightly faster in the sodium dodecyl sulfate dimension than did [beta]-tubulin. Nine [alpha]-tubulin isotypes that formed two distinct groups were identified on immunoblots of two-dimensional gels. The three most abundant [alpha]-tubulin isotypes were common to all tissues examined. Seven distinct [beta]-tubulin isotypes were also identified. Although their level of accumulation differed, four of the [beta]-tubulin isotypes were common to all tissues. Preferential accumulation of isotypes was more apparent in fibers than in the other tissues examined. Two [alpha]-tubulin isotypes and two [beta]-tubulin isotypes showed preferential accumulation in 10- and 20-d postanthesis fibers, respectively.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, P.O. Box 19687, New Orleans, Louisiana 70179.
authors.forename: D. C.
authors.initials: DC
authors.lastname: Dixon
authors.forename: R. W.
authors.initials: RW
authors.lastname: Seagull
authors.forename: B. A.
authors.initials: BA
authors.lastname: Triplett