Expression of a low-temperature-induced protein in Brassica napus

• Published in: Plant physiology (Bethesda) Vol. 108; no. 2; pp. 795 - 803
• Main Authors: Boothe, J.G. (University of Calgary, Calgary, Alberta, CA.), De Beus, M.D, Johnson-Flanagan, A.M
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01.06.1995
• Subjects: Acclimatization; ADAPTACION; ADAPTATION; ANALISIS CUANTITATIVO; ANALYSE QUANTITATIVE; ARN MENSAJERO; ARN MESSAGER; Biological and medical sciences; BRASSICA NAPUS; Complementary DNA; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; CONGELACION; CONGELATION; CONTENIDO PROTEICO; ELECTROLITOS; ELECTROLYTE; Electrolytes; ESTRUCTURA CELULAR; EXPRESION GENICA; EXPRESSION DES GENES; FEUILLE; Freezing; FRIO; FROID; Fundamental and applied biological sciences. Psychology; Gels; GENETICA; GENETIQUE; HOJAS; Leaves; Low temperature; Messenger RNA; Metabolism; Nitrogen metabolism; PERDIDAS; PERTE; Plant physiology and development; PROTEINAS; PROTEINE; RESISTANCE A LA TEMPERATURE; RESISTENCIA A LA TEMPERATURA; RNA; SINTESIS DE PROTEINAS; Spinach; STRUCTURE CELLULAIRE; SYNTHESE PROTEIQUE; TEMPERATURA; TEMPERATURE; TENEUR EN PROTEINES; Whole Plant, Environmental, and Stress Physiology; Temperature; Cruciferae; Protein synthesis; Dicotyledones; Angiospermae; Brassica napus; Spermatophyta; Recombinant DNA; Gene expression; Oil plant(vegetal); Frost resistance
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.108.2.795

BN28 is a low-temperature-induced, boiling-soluble protein in Brassica napus. We used antibodies raised against a recombinant BN28 to examine the expression of this protein in cold-acclimating plants and to investigate its relationship to plant freezing tolerance. Changes in the steady-state levels of BN28 protein appear to lag several days behind those of the mRNA. BN28 is first detected on immunoblots after approximately 8 d of exposure to low temperature, and thereafter levels remain stable while plants are maintained at 4 degrees C. Radiolabeling studies indicate that BN28 is synthesized at a relatively low rate. A decline in protein levels is observed soon after returning plants to control temperatures, and little or no protein can be detected after 7 d of deacclimation. The disappearance of the protein precedes a loss in freezing tolerance, suggesting that BN28 is not involved in maintaining plasma membrane integrity. Expression of BN28 is observed primarily in leaves and appears to be low-temperature specific. Quantitative analysis indicated that BN28 accumulates to approximately 82.7 pmol mg-1 total protein in cold-acclimated leaves. This concentration is similar to that reported for two group 2 late-embryogenesis-abundant-like proteins