Gutierrez C
Centro de Biologá Molecular 'Severo Ochoa', Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid, Cantoblanco, Spain.
Plant Mol Biol. 2000 Aug;43(5-6):763-72. doi: 10.1023/a:1006462028363.
Geminiviruses are plant DNA viruses with a small genome that infect a large variety of plant species. Viral proteins regulate viral DNA replication and transcription. Also they appear to have an impact on cellular gene expression. Cellular proteins directly involved in DNA replication, such as PCNA, have long been known to accumulate in cells expressing Rep tomato golden mosaic geminivirus. This effect can be a direct effect of the viral protein and/or be mediated by interference with the G1/S transition control, namely the pathway controlled by the retinoblastoma-related (RBR) protein, analogous to the human retinoblastoma (RB) tumour suppressor protein. Different geminiviruses seem to have evolved two mechanisms to interact with plant RBR proteins. One is dependent on a LxCxE amino acid motif present in proteins, such as RepA, encoded by members of the Mastrevirus genus, and another seems to be mediated by the viral Rep protein, which lacks the LxCxE motif, encoded by members of the Begomovirus, and perhaps the Curtovirus genus. These and other aspects of the relationships between geminivirus replication and cell cycle control pathways will be discussed.
双生病毒是一类植物DNA病毒，基因组较小，可感染多种植物物种。病毒蛋白调节病毒DNA的复制和转录。它们似乎还对细胞基因表达有影响。长期以来人们已知，直接参与DNA复制的细胞蛋白，如增殖细胞核抗原（PCNA），会在表达番茄金黄花叶双生病毒Rep的细胞中积累。这种效应可能是病毒蛋白的直接作用，和/或由干扰G1/S转换控制介导，即由视网膜母细胞瘤相关（RBR）蛋白控制的途径，类似于人类视网膜母细胞瘤（RB）肿瘤抑制蛋白。不同的双生病毒似乎已经进化出两种与植物RBR蛋白相互作用的机制。一种机制依赖于存在于蛋白（如由玉米线条病毒属成员编码的RepA）中的LxCxE氨基酸基序，另一种机制似乎由病毒Rep蛋白介导，该蛋白缺乏LxCxE基序，由菜豆金色花叶病毒属成员，可能还有曲顶病毒属成员编码。本文将讨论双生病毒复制与细胞周期控制途径之间关系的这些及其他方面。
