Extracellular accumulation of an auxin-regulated protein in Phaseolus vulgaris L. cell is inhibited by oligogalacturonides

Alpha-1,4-oligogalacturonides elicit a variety of plant defense responses and affect plant growth and development. Treatment of Phaseolus vulgaris L. suspension cultured cells with oligogalacturonides reduced the level of a 32 kD protein (p 32) that is accumulated in the culture medium in the presence of auxin but is not secreted under a condition of auxin starvation. Addition to bean cell suspension cultures of elicitors such as glucan and chitosan had no effect on the p 32 level. These data suggest that the regulation of p32 by oligogalacturonides may be important in plant growth and development as well as for plant defense responses.