An alpha-galactosidase with an essential function during leaf development.
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.
Chrost
Bozena
B
Institute of Botany, University of Kiel, Olshausenstrasse 40, 24089, Kiel, Germany.
Kolukisaoglu
Uener
U
Schulz
Burkhard
B
Krupinska
Karin
K
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D002473:Cell Wall / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000201:enzymology* / Q000254:growth & development*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010802:Phylogeny; D018515:Plant Leaves / Q000201:enzymology* / Q000254:growth & development*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000519:alpha-Galactosidase / Q000378:metabolism*
D010940:Plant Proteins; D000519:alpha-Galactosidase