A developmentally regulated hydroxyproline-rich glycoprotein from the cell walls of soybean seed coats

• Published in: Plant physiology (Bethesda) Vol. 77; no. 3; pp. 532 - 535
• Main Authors: Cassab, G.I, Nieto-Sotelo, J, Cooper, J.B, Van Holst, G, Varner, J.E
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01.03.1985
• Subjects: Agronomy. Soil science and plant productions; Amino acids; ANATOMIA DE LA PLANTA; ANATOMIE VEGETALE; Biological and medical sciences; Cell biochemistry; Cell physiology; Cell walls; COMPOSICION; COMPOSITION; Economic plant physiology; Flowering; Fructification, ripening. Postharvest physiology; Fundamental and applied biological sciences. Psychology; Gels; GLICOPROTEINAS; GLYCINE MAX; GLYCOPROTEINE; GLYCOPROTEINS; Growth and development; HIDROXIPROLINA; HYDROXYPROLINE; Mesophyll cells; PLANT ANATOMY; Plant physiology and development; Plants; SEED COATS; Seeds; Soybeans; Testa; Tegument; Seeds; Hydroxyproline; Glycoproteins; Glycine max; Cell wall; Oil plant(vegetal); Leguminosae; Dicotyledones; Angiospermae; High protein crop; Spermatophyta; Developmental stage
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.77.3.532

In soybean seeds the level of hydroxyproline is regulated in a developmental and tissue-specific manner. The seed coat contains approximately 77% of the total hydroxyproline in the seed at all stages of development. We determined the ratio of hydroxyproline to dry weight in a number of tissues within the seed; however, only the seed coat shows an increase in this ratio during development. Within the many cell layers of the seed coat, hydroxyproline is most abundant in the external layer. The hydroxyproline is present as an hydroxyproline-rich cell wall glycoprotein. The protein is rich in hydroxyproline (36%), lysine (11%), proline (10%), histidine (9%), tyrosine (9%), and serine (8%). The carbohydrate portion is 90 mole % arabinose and 10 mole % galactose. The arabinose residues are attached to hydroxyproline mostly in the form of trisaccharides. The apparent molecular weight of this glycoprotein is 100,000 daltons.