TRH1 encodes a potassium transporter required for tip growth in Arabidopsis root hairs.
Plant Cell
; 13(1): 139-51, 2001 Jan.
Article
en En
| MEDLINE
| ID: mdl-11158535
Root hair initiation involves the formation of a bulge at the basal end of the trichoblast by localized diffuse growth. Tip growth occurs subsequently at this initiation site and is accompanied by the establishment of a polarized cytoplasmic organization. Arabidopsis plants homozygous for a complete loss-of-function tiny root hair 1 (trh1) mutation were generated by means of the T-DNA-tagging method. Trichoblasts of trh1 plants form initiation sites but fail to undergo tip growth. A predicted primary structure of TRH1 indicates that it belongs to the AtKT/AtKUP/HAK K(+) transporter family. The proposed function of TRH1 as a K(+) transporter was confirmed in (86)Rb uptake experiments, which demonstrated that trh1 plants are partially impaired in K(+) transport. In line with these results, TRH1 was able to complement the trk1 potassium transporter mutant of Saccharomyces, which is defective in high-affinity K(+) uptake. Surprisingly, the trh1 phenotype was not restored when mutant seedlings were grown at high external potassium concentrations. These data demonstrate that TRH1 mediates K(+) transport in Arabidopsis roots and is responsible for specific K(+) translocation, which is essential for root hair elongation.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Potasio
/
Proteínas Portadoras
/
Genes de Plantas
/
Arabidopsis
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Raíces de Plantas
Idioma:
En
Revista:
Plant Cell
Asunto de la revista:
BOTANICA
Año:
2001
Tipo del documento:
Article
País de afiliación:
Grecia
Pais de publicación:
Reino Unido