title: Hormonal control of alpha-amylase gene expression in barley. Studies using a cloned CDNA probe.
abstract: Starting with an enriched alpha-amylase mRNA preparation, cDNA was synthesized by reverse transcription and was cloned at the Pst I site of plasmid vector pBR322 by the "G-C tailing" procedure. Clones containing alpha-amylase cDNA sequences were identified among the recombinant clones by in vitro translation of hybrid-selected mRNA followed by immunoprecipitation of translation products with antiserum to alpha-amylase. The longest alpha-amylase cDNA clone isolated was 630 base pairs long and was characterized by digestion with restriction enzymes. Using this clone as a labeled nucleic acid hybridization probe, we observed that multiple bands of DNA with alpha-amylase sequences were present in restriction digests of barley embryo DNA. This indicates the presence of a family of barley alpha-amylase or alpha-amylase-like genes. Analysis of RNA blots with the cloned alpha-amylase hybridization probe indicated that alpha-amylase mRNA is synthesized de novo in barley aleurones after addition of gibberellic acid. The gibberellic acid-induced accumulation of alpha-amylase mRNA is blocked by cycloheximide which suggests the requirement of a newly synthesized protein factor for efficient expression of alpha-amylase gene.
mesh_terms: D000681:Amylases / Q000235:genetics*; D001483:Base Sequence; D002499:Centrifugation, Density Gradient; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D005786:Gene Expression Regulation; D001467:Hordeum; D010944:Plants / Q000201:enzymology / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D000516:alpha-Amylases / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D004247:DNA; D000681:Amylases; D000516:alpha-Amylases