Reduced expression of a-tubulin genes in Arabidopsis thaliana specificallyaffects root growth and morphology, root hair development and root gravitropism

Citation
Yq. Bao et al., Reduced expression of a-tubulin genes in Arabidopsis thaliana specificallyaffects root growth and morphology, root hair development and root gravitropism, PLANT J, 28(2), 2001, pp. 145-157
Citations number
41
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences","Animal & Plant Sciences
Journal title
PLANT JOURNAL
ISSN journal
0960-7412 → ACNP
Volume
28
Issue
2
Year of publication
2001
Pages
145 - 157
Database
ISI
SICI code
0960-7412(200110)28:2<145:REOAGI>2.0.ZU;2-S
Abstract
Different alpha -tubulin cDNA sequences fused in an antisense orientation t o a CaMV 35S promoter were introduced into Arabidopsis thaliana plants. Sev eral independent transgenic lines that showed a moderate but clear reductio n of alpha -tubulin gene expression (TUA6/AS lines) were obtained and pheno typically characterized. Although no apparent abnormalities were detected i n the aerial parts of TUA6/AS plants, root development was severely affecte d. Cells in TUA6/AS root tips were found to contain aberrant microtubular s tructures, to expand abnormally and to be unable to undergo regular cell di vision. These cellular defects caused a dramatic radial expansion of the ro ot tip and inhibited root elongation. In addition, TUA6/AS roots displayed ectopic formation of root hairs, root hair branching and a reduced ability to respond to gravitropic challenges. Our results contribute to an improved understanding of the different roles microtubules play during root develop ment and demonstrate that reverse genetics is a powerful tool to analyze cy toskeletal functions during plant organogenesis.