Fig. 1. Specific expression of Rec8 protein in meiosis-undergoing testis, as revealed by an anti-mouse Rec8 antibody. (A) The anti-mouse Rec8 antibody was raised in a rabbit against the bacterially expressed C-terminal fragment of mouse Rec8 protein. The antigenic C-terminal mouse Rec8 protein (C-terminal Rec8) and nuclear extracts from mouse testis (Testis nuclei) were subjected to western blotting with the anti-Rec8 antibody after pre-absorption of the antibody with (+) or without (-) the antigen. (B) Testis nuclear extracts were immunoprecipitated with anti-Rec8 antibody and treated with (+) or without (-) either alkaline PPase or -PPase. The immunoprecipitates were separated by SDS-PAGE and subjected to western blotting with anti-Rec8 antibody. (C) Nuclear extracts from various mouse tissues were subjected to western blotting with anti-SMC1, anti-SMC3, anti-Rec8 and anti-SCP3 antibodies. K, kidney; L, liver; T, testis. (D) Testis extracts from 0-, 1-, 2-, 3-, and 5-week-old mice were examined in western blotting with anti-SMC1, anti-SMC3, anti-Rec8, anti-SCP3 and anti-tubulin antibodies. Closed arrowheads indicate SMC1, SMC3, Rec8, SCP3 and tubulin protein in the respective blots, while an open arrowhead indicates SMC1ß protein.