Changes in the Protein Composition of the Shoot Apical Bud of Sinapis alba in Transition to Flowering

Abstract

Vegetative plants of Sinapis alba L. grown in short days were induced to flower by exposure to one or continuous long days. In both inductive conditions, the first flowers were initiated about 60 h after the start of the treatment. Soluble protein extracts were prepared from apical buds and just-expanded leaves of both vegelative and induced plants. Rabbit anlisera were prepared using extracts from vegetative and reproductive buds. Immunodiffusion tests were performed. Analysis of the precipitin bands indicated that: (I) one antigcnic protein was present in the vegetative buds and disappeared from the buds of induced plants between 96 and 240 h after the start of the inductive treatment; (2) the concentration of another antigenic protein increa.sed in buds of induced plants 30 h after ihe start ofthe induclive treatment: (3) the concentration ofa third antigenic protein increased in buds of indueed plants at 96 h.

Floral events inSilene coeli-rosa

“…However, the timing of this new gene expression is controversial. In Sinapis, antigenic proteins, unique to the reproductive bud, were detected (Pierard et al, 1977) and new proteins were resolved using two-dimensional gel electrophoresis (Lyndon et al, 1983). If differences were detected between induced and non-induced plants, the changes were related to the maturation of flowering parts rather than to evocation.…”

“…Following an inductive treatment, in the buds of Sinapis alba, one antigenic protein disappeared (Pierard et al, 1977) and the concentration of two other antigenic proteins increased. In the apices of Xanthium strumarium (Kannangara et al, 1990), a photoinductive short-day treatment was associated with the disappearance of two polypeptides (9 kDa and 34 kDa).…”