Figure 3.
TRAB1 Is Phosphorylated Rapidly in Response to ABA.
Rice suspension-cultured cells (Oc) were labeled with 32Pi for 1 h. Cells then were treated with 50 μM ABA. Nuclear extracts were prepared from the labeled cells and subjected to immunoprecipitation with anti-TRAB1 antibody followed by SDS-PAGE.
(A) After ABA treatment for 30 min, immunoprecipitation was performed with preimmune serum (P), anti-TRAB1 antibody (AnT), or anti-TRAB1 antibody preincubated with an excess amount of recombinant TRAB1 (AnT+T). The position of the 45-kD TRAB1 band is indicated by the arrow. The smaller minor bands indicated by asterisks are considered to be immunologically related to TRAB1. However, it is not known whether they are partially degraded forms of TRAB1 or the products of related genes.
(B) Immunoprecipitation with anti-TRAB1 antibody using nuclear extracts from the labeled cells treated with ABA for the indicated times.