Developmentally related responses of maize catalase genes to salicylic acid

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 92; no. 13; pp. 5930 - 5934
• Main Authors: Guan, L. (North Carolina State University, Raleigh, NC.), Scandalios, J.G
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 20-06-1995; National Acad Sciences; National Academy of Sciences
• Subjects: ACIDE SALICYLIQUE; ACIDO SALICILICO; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; ARN MENSAJERO; ARN MESSAGER; Botany; CATALASA; CATALASE; Catalase - biosynthesis; Catalase - genetics; Catalase - metabolism; Corn; DESARROLLO EMBRIONARIO; Developmental stages; DEVELOPPEMENT EMBRYONNAIRE; Embryogenesis; Embryos; EXPRESION GENICA; EXPRESSION DES GENES; GENE; Gene Expression Regulation, Enzymologic - drug effects; GENES; Genes, Plant - drug effects; GENETICA; GENETIQUE; GERMINACION; GERMINATION; Hydrogen; ISOENZIMAS; ISOENZYME; Isoenzymes - biosynthesis; Isoenzymes - genetics; Isoenzymes - metabolism; Kinetics; Leaves; Peroxides; RNA; RNA, Plant - isolation & purification; RNA, Plant - metabolism; Salicylates - pharmacology; Salicylic Acid; Seeds; Transcription, Genetic; ZEA MAYS; Zea mays - enzymology; Zea mays - genetics; Zea mays - growth & development
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.92.13.5930

The response of the maize catalase genes (Cat1, Cat2, and Cat3) to salicylic acid (SA) was examined at two distinct developmental stages: embryogenesis and germination. A unique, germination-related differential response of each maize catalase gene to various doses of SA was observed. During late embryogenesis, total catalase activity in scutella increased dramatically with 1 mM SA treatment. The accumulation of Cat2 transcript and CAT-2 isozyme protein provided the major contribution to the observed increase in total catalase activity. This increase was paralleled by the enhanced growth of germinated embryos at that stage. In a CAT-2 null mutant line, a full compensation of total catalase activity by the CAT-1 isozyme was observed in the presence of SA. This suggests that catalase is important for maintenance of normal cellular processes under stress conditions. SA at 1 mM, which enhances growth of precociously germinated embryos, appeared to inhibit seed germination at 1 day after imbibition. Furthermore, Cat2 transcript accumulation was inhibited at this stage. SA is probably not a direct signal for the induction of the catalase genes. Other signals, possibly germination-related regulator(s), might be responsible for the induction of the catalase genes. The effect of SA on the activity of purified catalase protein was also examined