| Title | The Arabidopsis D-Type Cyclin CYCD2;1 and the Inhibitor ICK2/KRP2 Modulate Auxin-Induced Lateral Root Formation |
| Publication Type | Journal Article |
| 2011 |
| Authors | Sanz, L, Dewitte, W, Forzani, C, Patell, F, Nieuwland, J, Wen, B, Quelhas, P, de Jager, S, Titmus, C, Campilho, A, Ren, H, Estelle, M, Wang, H, Murray, JAH |
| Journal | Plant CellPlant Cell |
| Volume | 23 |
| Issue | 2 |
| Pagination | 641 - 660 |
| Date Published | 2011/// |
| 10404651 (ISSN) |
| Arabidopsis, Arabidopsis protein, Arabidopsis Proteins, Arabidopsis thaliana, article, ATP dependent 26S protease, cell cycle, cell cycle protein, Cell Cycle Proteins, cell nucleus, CycD2 protein, Arabidopsis, cycline, Cyclins, gene expression regulation, Gene Expression Regulation, Plant, genetics, growth, development and aging, ICK2 protein, Arabidopsis, indoleacetic acid derivative, Indoleacetic Acids, metabolism, mutation, plant root, Plant roots, proteasome, Proteasome Endopeptidase Complex |
| The integration of cell division in root growth and development requires mediation of developmental and physiological signals through regulation of cyclin-dependent kinase activity. Cells within the pericycle form de novo lateral root meristems, and D-type cyclins (CYCD), as regulators of the G 1-to-S phase cell cycle transition, are anticipated to play a role. Here, we show that the D-type cyclin protein CYCD2;1 is nuclear in Arabidopsis thaliana root cells, with the highest concentration in apical and lateral meristems. Loss of CYCD2;1 has a marginal effect on unstimulated lateral root density, but CYCD2;1 is rate-limiting for the response to low levels of exogenous auxin. However, while CYCD2;1 expression requires sucrose, it does not respond to auxin. The protein Inhibitor-Interactor of CDK/Kip Related Protein2 (ICK2/KRP2), which interacts with CYCD2;1, inhibits lateral root formation, and ick2/krp2 mutants show increased lateral root density. ICK2/ KRP2 can modulate the nuclear levels of CYCD2;1, and since auxin reduces ICK2/KRP2 protein levels, it affects both activity and cellular distribution of CYCD2;1. Hence, as ICK2/KRP2 levels decrease, the increase in lateral root density depends on CYCD2;1, irrespective of ICK2/CYCD2;1 nuclear localization. We propose that ICK2/KRP2 restrains root ramification by maintaining CYCD2;1 inactive and that this modulates pericycle responses to auxin fluctuations. © 2011 American Society of Plant Biologists.
|
| http://www.scopus.com/inward/record.url?eid=2-s2.0-79953123085&partnerID=40&md5=f1355f64db2bcf9f2d881104f23005eb |
