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An alpha-galactosidase with an essential function during leaf development.

Bozena Chrost·Uener Kolukisaoglu·Burkhard Schulz·Karin Krupinska
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Abstract

The putative alpha-galactosidase gene HvSF11 of barley, previously shown to be expressed during dark induced senescence, is expressed in the growing/elongating zone of primary foliage leaves of barley. The amino acid sequence deduced from the full length HvSF11 cDNA contains a hydrophobic signal sequence at the N-terminus. Phylogenetic relationship of the HvSF11 encoded barley alpha-galactosidase to other alpha-galactosidases revealed high homology with the alpha-galactosidase encoded by the gene At5g08370 from Arabidopsis thaliana. We have isolated two independent heterozygous At5g08370 T-DNA insertion mutants from Arabidopsis thaliana, both of which have a higher number of rosette leaves with a curly surface leaf morphology and delayed flowering time in comparison to wildtype plants. Localization of the Arabidopsis alpha-galactosidase protein via GUS-tag revealed that the protein is associated with the cell wall. This result was confirmed by immunological detection of the orthologous barley protein in a protein fraction derived from cell walls of barley leaves. It is concluded that the alpha-galactosidase proteins from barley and Arabidopsis might fulfill an important role in leaf development by functioning in cell wall loosening and cell wall expansion.

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Amino Acid SequenceArabidopsisCell WallGene Expression Regulation, PlantHordeumMolecular Sequence DataMutagenesis, InsertionalPhylogenyPlant LeavesPlant Proteinsalpha-GalactosidaseJournal ArticleResearch Support, Non-U.S. Gov't

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Bozena Chrost, Uener Kolukisaoglu, Burkhard Schulz, Karin Krupinska. 2006-07-15. An alpha-galactosidase with an essential function during leaf development.. https://doi.org/10.1007/s00425-006-0350-9

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