Protease activities in non embryogenic and embryogenic carrot daucus carota cell strains during callus growth and embryo formation
Carlberg, I.; Soderhall, K.; Glimelius, K.; Eriksson, T.
Physiologia Plantarum 62(3): 458-464
Embryogenic and non-embryogenic cell strains of D. carota L. were examined for their protease activity using a wide range of chromogenic synthetic peptides as substrates. High arginine-specific activity was present in all strains, but no protease activity specific for embryogenic or non-embryogenic strains could be detected with the substrates tested. The specific protease activity was 5-10 times higher in the non-embryogenic as compared to the embryogenic strain for most tested substrates, and this difference was not due to release of proteases in the latter. All strains showed a decrease in protease activity when cultured in media without 2,4-D, but the embryos had high protease activity in comparison with the non-differentiated cell aggregates. In the latter aggregates, hydrolyzing activity towards 3 of the substrates (H-D-Phe-Pip-Arg-p-nitroanilide, Suc-Ala-Pro-Phe-p-nitroanilide and Bz-Phe-Val-Arg-p-nitroanilide) was absent, whereas the embryos were able to hydrolyze them.