Cell cycle -dependent proteolysis in plants. Identification Of the destruction box pathway and metaphase arrest produced by the proteasome inhibitor mg132

@article{citeulike:235354, abstract = {It is widely assumed that mitotic cyclins are rapidly degraded during anaphase, leading to the inactivation of the cell cycle-dependent protein kinase Cdc2 and allowing exit from mitosis. The proteolysis of mitotic cyclins is ubiquitin/26S proteasome mediated and requires the presence of the destruction box motif at the N terminus of the proteins. As a first attempt to study cyclin proteolysis during the plant cell cycle, we investigated the stability of fusion proteins in which the N-terminal domains of an A-type and a B-type tobacco mitotic cyclin were fused in frame with the chloramphenicol acetyltransferase (CAT ) reporter gene and constitutively expressed in transformed tobacco BY2 cells. For both cyclin types, the N-terminal domains led the chimeric cyclin-CAT fusion proteins to oscillate in a cell cycle-specific manner. Mutations within the destruction box abolished cell cycle-specific proteolysis. Although both fusion proteins were degraded after metaphase, cyclin A-CAT proteolysis was turned off during S phase, whereas that of cyclin B-CAT was turned off only during the late G2 phase. Thus, we demonstrated that mitotic cyclins in plants are subjected to post-translational control (e.g., proteolysis). Moreover, we showed that the proteasome inhibitor MG132 blocks BY2 cells during metaphase in a reversible way. During this mitotic arrest, both cyclin-CAT fusion proteins remained stable.}, address = {Institut de Biologie Moleculaire des Plantes du CNRS, 12 rue du General Zimmer, 67084 Strasbourg Cedex, France.}, author = {Genschik, P. and Criqui, M. C. and Parmentier, Y. and Derevier, A. and Fleck, J. }, citeulike-article-id = {235354}, issn = {1040-4651}, journal = {Plant Cell}, keywords = {cell-cycle, plant, proteasome}, month = {December}, number = {12}, pages = {2063--2076}, posted-at = {2005-06-23 14:29:33}, priority = {2}, title = {Cell cycle -dependent proteolysis in plants. Identification Of the destruction box pathway and metaphase arrest produced by the proteasome inhibitor mg132 }, url = {http://view.ncbi.nlm.nih.gov/pubmed/9836745}, volume = {10}, year = {1998} }

TY - JOUR ID - citeulike:235354 L3 - citeulike-article-id:235354 TI - Cell cycle -dependent proteolysis in plants. Identification Of the destruction box pathway and metaphase arrest produced by the proteasome inhibitor mg132 JF - Plant Cell VL - 10 IS - 12 SP - 2063 EP - 2076 AD - Institut de Biologie Moleculaire des Plantes du CNRS, 12 rue du General Zimmer, 67084 Strasbourg Cedex, France. SN - 1040-4651 N2 - It is widely assumed that mitotic cyclins are rapidly degraded during anaphase, leading to the inactivation of the cell cycle-dependent protein kinase Cdc2 and allowing exit from mitosis. The proteolysis of mitotic cyclins is ubiquitin/26S proteasome mediated and requires the presence of the destruction box motif at the N terminus of the proteins. As a first attempt to study cyclin proteolysis during the plant cell cycle, we investigated the stability of fusion proteins in which the N-terminal domains of an A-type and a B-type tobacco mitotic cyclin were fused in frame with the chloramphenicol acetyltransferase (CAT ) reporter gene and constitutively expressed in transformed tobacco BY2 cells. For both cyclin types, the N-terminal domains led the chimeric cyclin-CAT fusion proteins to oscillate in a cell cycle-specific manner. Mutations within the destruction box abolished cell cycle-specific proteolysis. Although both fusion proteins were degraded after metaphase, cyclin A-CAT proteolysis was turned off during S phase, whereas that of cyclin B-CAT was turned off only during the late G2 phase. Thus, we demonstrated that mitotic cyclins in plants are subjected to post-translational control (e.g., proteolysis). Moreover, we showed that the proteasome inhibitor MG132 blocks BY2 cells during metaphase in a reversible way. During this mitotic arrest, both cyclin-CAT fusion proteins remained stable. KW - cell-cycle KW - plant KW - proteasome AU - Genschik, P AU - Criqui, MC AU - Parmentier, Y AU - Derevier, A AU - Fleck, J PY - 1998/12// UR - http://view.ncbi.nlm.nih.gov/pubmed/9836745 ER -