Inhibition of cell wall autolysis and auxin‐induced elongation of Cicer arietinum epicotyls by β‐galactosidase antibodies

Abstract

Polyclonal antibodies were raised in response to βIII‐galactosidase purified from cell wall of Cicer arietinum epicotyls. The antibody preparation generated, bound to βIII protein giving a major protein band in the zone corresponding to Mr 45 000, the molecular mass previously estimated for βIII‐galactosidase. These antibodies clearly suppress autolytic reactions in isolated walls of Cicer arietinum epicotyl segments, while the preimmune serum had no effect on autolytic reaction. The results strongly support the idea that the autolytic degradation of the cell wall is carried out by the βIII‐galactosidase.The antibodies against β‐galactosidase were also able to inhibit cell wall hydrolysis mediated by both total cell wall protein extracted by LiCl and cell wall hydrolysis mediated by βIII‐galactosidase.Since autolysis is thought to be related to the process of cell wall loosening, the effects of the antibodies against the autolytic enzyme was also tested on epicotyl growth. β‐galactosidase antibodies consistently inhibited IAA‐induced elongation.