Gutierrez C
Centro de Biología Molecular 'Severo Ochoa', Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid (UAM), Cantoblanco, 28049 Madrid, Spain.
EMBO J. 2000 Mar 1;19(5):792-9. doi: 10.1093/emboj/19.5.792.
Plant cell growth and development depend on continuous cell proliferation which is restricted to small regions of the plant called meristems. Infection by geminiviruses, small DNA viruses whose replicative cycle relies on host cell factors, is excluded from those proliferating areas. Since most of the replicative factors are present, almost exclusively, in proliferating cells, geminivirus infection is believed to induce a cellular state permissive for viral DNA replication, e.g. S-phase or, at least, some specific S-phase functions. The molecular basis for this effect seems to be the interference that certain geminivirus proteins exert on the retinoblastoma-related (RBR) pathway, which analogously to that of animal cells, regulates plant cell cycle activation and G(1)-S transition. In some cases, geminiviruses induce cell proliferation and abnormal growth. Mechanisms other than sequestering plant RBR probably contribute to the multiple effects of geminivirus proteins on cellular gene expression, cell growth control and cellular DNA replication. Current efforts to understand the coupling of geminivirus DNA replication to cell cycle and growth control as well as the directions in which future research is aiming are reviewed.
植物细胞的生长和发育依赖于持续的细胞增殖，而这种增殖仅限于植物中称为分生组织的小区域。双生病毒是一类小型DNA病毒，其复制周期依赖于宿主细胞因子，这类病毒的感染被排除在这些增殖区域之外。由于大多数复制因子几乎只存在于增殖细胞中，因此双生病毒感染被认为会诱导一种允许病毒DNA复制的细胞状态，例如S期，或者至少是一些特定的S期功能。这种效应的分子基础似乎是某些双生病毒蛋白对视网膜母细胞瘤相关（RBR）途径的干扰，该途径与动物细胞类似，调节植物细胞周期激活和G(1)-S转换。在某些情况下，双生病毒会诱导细胞增殖和异常生长。除了隔离植物RBR之外，其他机制可能也导致了双生病毒蛋白对细胞基因表达、细胞生长控制和细胞DNA复制的多种影响。本文综述了目前在理解双生病毒DNA复制与细胞周期及生长控制之间的联系方面所做的努力，以及未来研究的方向。
