Abstract The anther proteins in uninucleate-stage and binucleate-stage from wheat male sterile line induced by CHA SQ-1 were separated by two-dimensional electrophoresis with immobilized pH(4~7) gradients as the first dimension and SDS-PAGE as the second. After Coomassie Blue G-250 staining and analysis by PDQuest 2DE software, over 500 protein spots were detected reproducibly, and these protein spots mainly focused on pI5~ 6, molecular weight ranging from 20.0kD to 40.0kD. 43 in uninucleate-stage and 45 in binucleate-stage differentially expressed protein spots were detected by PDQuest 2DE software, Molecular weight and pI of these spots were calculated. Among these, in uninucleate-stage, 11 protein spots were absent in the protein map of treatment anther but present in that of check, 7 present in that of check but absent in that of treatment, 14 and 11 up-regulated significantly in that of treatment in comparison with that of check; in binucleate-stage, 13 protein spots were absent in the protein map of treatment anther but present in that of check, 7 present in that of check but absent in that of treatment, 12 down-regulated and 13up-regulated significantly in that of treatment. The protein spots A-Z3（26.8/5.7）in uninucleate-stage and C-Z5（26.8/5.7）in binucleate-stage were absent in the protein map of treatment anther. The spot A-L10(26.8/5.9) of treatment anther in uninucleate-stage was down-regulated but spot C-Z6（26.9/5.9）absent in binucleate-stage. These differential proteins may participate in pollen development process directly or indirectly. It can be deduced that the differentially expressed protein spots might relate to male sterility induced by CHA-SQ-1.
