Analysis of the state of posttranslational calmodulin methylation in developing pea plants. [Pisum sativum]

Journal Article · Sun Jul 01 00:00:00 EDT 1990 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.93.3.880· OSTI ID:5858317

Oh, Sukheung; Roberts, D M ^[1]

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1. Univ. of Tennessee, Knoxville (USA)

A specific calmodulin-N-methyltransferase was used in a radiometric assay to analyze the degree of methylation of lysine-115 in pea (Pisum sativum) plants. Calmodulin was isolated from dissected segments of developing roots of young etiolated and green pea plants and was tested for its ability to be methylated by incubation with the calmodulin methyltransferase in the presence of ({sup 3}H)methyl-S-adenosylmethionine. By this approach, the presence of unmethylated calmodulins were demonstrated in pea tissues, and the levels of methylation varied depending on the developmental state of the tissue tested. Calmodulin methylation levels were lower in apical root segments of both etiolated and green plants, and in the young lateral roots compared with the mature, differentiated root tissues. The incorporation of methyl groups into these calmodulin samples appears to be specific for position 115 since site-directed mutants of calmodulin with substitutions at this position competitively inhibited methyl group incorporation. The present findings, combined with previous data showing differences in the ability of methylated and unmethylated calmodulins to activate pea NAD kinase raise the possibility that posttranslational methylation of calmodulin could be another mechanism for regulating calmodulin activity.

• OSTI ID: 5858317
• Journal Information: Plant Physiology; (USA), Vol. 93:3; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALMODULIN
POST-TRANSLATION MODIFICATION
METHYL TRANSFERASES
BIOCHEMICAL REACTION KINETICS
LYSINE
METHIONINE
METHYLATION
MUTANTS
PISUM
ROOTS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
AMINO ACIDS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
DRUGS
ENZYMES
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LEGUMINOSAE
LIPOTROPIC FACTORS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PLANTS
PROTEINS
REACTION KINETICS
TRANSFERASES
550201* - Biochemistry- Tracer Techniques