Cloning of cDNA for a cell wall-bound acid invertase from tomato (Lycopersicon esculentum) and expression of soluble and cell wall-bound invertases in plants and wounded leaves of L. esculentum and L. peruvianum.
A cDNA, Wiv-1, for an isozyme of acid invertase (EC 3.2.1.26) was cloned from wounded leaves of tomato (Lycopersicon esculentum). The encoded protein had a basic isoelectric point and strong similarity to the amino acid sequences of plant cell wall-bound invertases. The conserved sequence WECPD that is found in all plant cell wall-bound invertases was also found in the deduced protein. These results suggested that Wiv-1 encoded a cell wall-bound acid invertase of tomato. Wounding increased the levels of mRNAs for soluble and cell wall-bound invertases and the activities of these invertases in leaves of L. esculentum and of a related species, L. peruvianum. The induction of Aiv-1 mRNA for the soluble enzyme in wounded leaves was not very strong, while that of Wiv-1 mRNA for the wall-bound enzyme was prominent. The level of Aiv-1 mRNA reached a maximum 48 h after wounding while that of Wiv-1 mRNA continued to rise for up to 96 h. These findings suggested that the genes for the two isozymes responded independently to wounding. The levels in various organs of Aiv-1 and Wiv-1 mRNAs were higher in L. esculentum than in L. peruvianum. Possible roles of cell wall-bound acid invertase in wound response and in developing plant are discussed.
Ohyama
A
A
National Research Institute of Vegetables, Ornamental Plants and Tea (NIVOT), Mie, Japan.
Nishimura
S
S
Hirai
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D002473:Cell Wall; D003001:Cloning, Molecular; D018076:DNA, Complementary; D018744:DNA, Plant; D015870:Gene Expression; D006026:Glycoside Hydrolases / Q000235:genetics*; D018551:Solanum lycopersicum / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D018515:Plant Leaves; D016133:Polymerase Chain Reaction; D018749:RNA, Plant / Q000032:analysis; D012995:Solubility; D043324:beta-Fructofuranosidase
D018076:DNA, Complementary; D018744:DNA, Plant; D018749:RNA, Plant; D006026:Glycoside Hydrolases; D043324:beta-Fructofuranosidase