Premium
Antisense‐inhibition of ADP‐glucose pyrophosphorylase in developing seeds of Vicia narbonensis moderately decreases starch but increases protein content and affects seed maturation
Author(s) -
Weber Hans,
Rolletschek Hardy,
Heim Ute,
Golombek Sabine,
Gubatz Sabine,
Wobus Ulrich
Publication year - 2000
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1046/j.1365-313x.2000.00853.x
Subject(s) - legumin , vicilin , storage protein , vicia faba , starch , cotyledon , biology , amylopectin , biochemistry , complementary dna , sucrose synthase , amylose , botany , sucrose , gene , invertase
Summary The small subunit of a Vicia faba ADP‐glucose pyrophosphorylase (AGP) cDNA was expressed in antisense orientation in Vicia narbonensis under the control of the seed‐specific legumin B4 promoter. From several independent transgenic lines both ADP‐glucose pyrophosphorylase AGP‐mRNA and AGP enzyme activity were reduced by up to 95% in the cotyledons during the mid‐ to late‐maturation phase. Starch was moderately decreased and sucrose was increased. In two of three lines, transcripts encoding the large subunit of AGP and the storage protein vicilin were increased, whereas legumin B‐mRNA was decreased. Transcripts of other storage‐associated genes were not altered. The cotyledons contained more protein and total nitrogen. Despite the reduction in starch, total carbon was not decreased and dry weight was unchanged. Compared to the wild type, transgenic seeds contained more water and accumulated dry weight during a longer period, and therefore had a prolonged seed‐filling period. Transgenic cotyledon cells of comparable age to the wild type were more highly vacuolated and contained smaller starch grains, indicating a delay in cellular differentiation. We conclude that a specific alteration in carbon metabolism can have pleiotropic effects on water and nitrogen content and induces temporal changes in seed development.