Two-dimensional electrophoresis of Cereus peruvianus callus tissues grown i
n culture media containing two different 2,4-dichlorophenoxyacetic acid (2,
4-D) and kinetin combinations was used to identify minor differences in pol
ypeptide composition of these cell clones. Altered expression during growth
in the two 2,4-D and kinetin combinations was apparent for 13 polypeptides
when calluses in the two media were compared. The number of proteins with
differential expression (presence or absence of specific spots) was higher
in callus tissues cultured in the 4.0 mg/L 2,4-D and 8.0 mg/L kinetin combi
nation than in callus tissues cultured in the 4.0 mg/L 2,4-D and 4.0 mg/L k
inetin combination. The present results show that the callus tissues mainta
ined at 4.0 mg/L 2,4-D and 8.0 mg/L kinetin can be used as a matrix for in
vitro selection programs.