Development of antibodies against secoisolariciresinol--application to the immunolocalization of lignans in Linum usitatissimum seeds.
Lignans are widely distributed plant metabolites associated with a large range of biological activities. In order to gain insight into their biosynthesis and their spatio-temporal accumulation an immunological probe was developed. Secondary metabolites generally have too small molecular weight to be antigenic and have to be associated with a carrier protein. Secoisolariciresinol was chosen as the hapten and was linked to bovine serum albumin via a spacer arm, the p-aminohippuric acid. The artificial antigen was injected to New Zealand rabbits. The successful production of polyclonal antibodies against secoisolariciresinol was assessed with indirect enzyme immunosorbent assay (ELISA) by comparison with pre-immune serum and by competitive assays using dilutions of secoisolariciresinol standards. The antibodies had an IC(50) value of 94 μg/ml and showed moderate cross-reactivities with structurally related compounds. They were thus used to immunolocalize lignans in flaxseed (Linum usitatissimum), one of the richest sources of lignans. The immunohistochemical labeling allowed us to localize for the first time lignans in planta. They are mainly localized in the secondary wall of the sclerite cells of the outer integument of the seed. A very light labeling is also observed in cytoplasmic inclusions of the endosperm. The results were correlated with HPLC analytical results which enabled to evaluate the relative lignan quantities: in flaxseed about 90% of the metabolites are localized in the outer integument.
Attoumbré
Jacques
J
Université de Picardie Jules Verne, EA3900-BioPI Biologie des Plantes et contrôle des Insectes ravageurs, Faculté de Pharmacie, 1 rue des Louvels, 80037 Amiens cedex, France.
Bienaimé
Christophe
C
Dubois
Frédéric
F
Fliniaux
Marc-André
MA
Chabbert
Brigitte
B
Baltora-Rosset
Sylvie
S
D000818:Animals; D000906:Antibodies / Q000032:analysis / Q000378:metabolism*; D002072:Butylene Glycols / Q000032:analysis* / Q000276:immunology*; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D019597:Flax / Q000737:chemistry / Q000276:immunology*; D017705:Lignans / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D011817:Rabbits; D012639:Seeds / Q000737:chemistry / Q000276:immunology
D000906:Antibodies; D002072:Butylene Glycols; D017705:Lignans; C060283:secoisolariciresinol