Analysis of the heat-shock protein pattern during somatic embryogenesis of carrot.

The pattern of proteins synthesized by carrot cells after heat-shock was analyzed by SDS-polyacrylamide gel electrophoresis. A study was made of the time of appearance and disappearance of the heat-shock bands and a comparison was made of the heat-shock proteins present in cell extracts obtained from cell suspensions, callus, protoplasts and the different stages of somatic embryogenesis.From this comparison a number of differences and hence of stage-specific markers could be seen. This type of analysis was also carried out in the presence of α-amanitin in order to get information on the type of control of heat-shock protein synthesis. It turned out that in all stages after the initial globular stage, α-amanitin does not alter the heat-shock protein pattern suggesting pre-existence of the relative mRNA's.