Arabidopsis thaliana PDX1.2 is critical for embryo development and heat shock tolerance
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PDX1.2 is expressed in the basal part of the globular-stage embryo, and plays critical roles in development, hypocotyl elongation, and stress response.
The Arabidopsis thaliana PDX1.2 protein belongs to a small family of three members. While PDX1.1 and PDX1.3 have been extensively described and are well established to function in vitamin B6 biosynthesis, the biological role of PDX1.2 still remains elusive. Here, we show that PDX1.2 is expressed early in embryo development, and that heat shock treatment causes a strong up-regulation of the gene. Using a combined genetic approach of T-DNA insertion lines and expression of artificial micro RNAs, we can show that PDX1.2 is critically required for embryo development, and for normal hypocotyl elongation. Plants with reduced PDX1.2 expression also display reduced primary root growth after heat shock treatments. The work overall provides a set of important new findings that give greater insights into the developmental role of PDX1.2 in plants.
KeywordsEmbryo development Heat shock response PDX family Pyridoxal-5-phosphate synthase Vitamin B6
Gene accession numbers
We would like to thank Dipika Jadav for technical support. This work was supported by DFG Grant HE3224/6–1 and NSF Grant MCB-1020673 to H.H.
Conflict of interest
The authors declare that they have no conflict of interest.
- Gonzalez E, Danehower D, Daub ME (2007) Vitamer levels, stress response, enzyme activity, and gene regulation of Arabidopsis lines mutant in the pyridoxine/pyridoxamine 5′-phosphate oxidase (PDX3) and the pyridoxal kinase (SOS4) genes involved in the vitamin B6 salvage pathway. Plant Physiol 145:985–996PubMedCentralPubMedCrossRefGoogle Scholar
- Wagner S, Bernhardt A, Leuendorf JE, Drewke C, Lytovchenko A, Mujahed N, Gurgui C, Frommer WB, Leistner E, Fernie AR, Hellmann H (2006) Analysis of the Arabidopsis rsr4-1/pd1-3 mutant reveals the critical function of the PDX1 protein family in metabolism, development, and vitamin B6 biosynthesis. Plant Cell 18:1722–1735PubMedCentralPubMedCrossRefGoogle Scholar