Structure and expression of a barley acidic beta-glucanase gene.
A barley acidic beta-1,3-glucanase gene was recovered from a barley genomic library by homology with a partial cDNA of barley basic beta-1,3-glucanase isoenzyme GII. The gene, Abg2, is homologous to the PR2 family of pathogenesis-related beta-1,3-glucanase genes. The ABG2 protein has 81% amino acid similarity to barley basic beta-1,3-glucanase GII. The ABG2 protein is encoded as a preprotein of 336 amino acids including a 28 amino acid signal peptide. A 299 bp intron occurs within codon 25. The mature ABG2 protein has a predicted mass of 32,642 Da and a calculated isoelectric point of 4.9. The second exon of the Abg2 gene shows a strong preference for G + C in the third position of degenerate codons. The Abg2 gene was functionally expressed in Escherichia coli. Abg2 mRNA is constitutively expressed in barley root; leaf expression of Abg2 mRNA is induced by mercuric chloride and infection by Erysiphe graminis f. sp. hordei. Southern blot analysis indicates that Abg2 is a member of a small gene family.
Malehorn
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Monsanto Agricultural Group, New Products Division, St. Louis, MO 63198.
Scott
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KJ
Shah
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D000143:Acids; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D017343:Genes, Plant / Q000235:genetics*; D016678:Genome; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000096:biosynthesis / Q000235:genetics*; D001467:Hordeum / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis; D015183:Restriction Mapping; D012639:Seeds / Q000201:enzymology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D000143:Acids; D010940:Plant Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C053376:pathogenesis-related proteins, plant; D004693:Glucan Endo-1,3-beta-D-Glucosidase