Moriyama H, Kanaya K, Wang J Z, Nitta T, Fukuhara T
Laboratory of Molecular Cell Biology, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Japan.
Plant Mol Biol. 1996 Jul;31(4):713-9. doi: 10.1007/BF00019459.
A very restricted amount of high-molecular-weight double-stranded RNA (dsRNA) has been found in healthy japonica rice plants. We discriminated dsRNA-carrying rice plants from noncarriers. The endogenous dsRNA was localized in the cytoplasm (about 100 copies per cell) and was transmissible to progeny plants by mating. In crosses between carriers and noncarriers, the RNA was transmitted efficiently to F1 plants via both egg and pollen. The rice dsRNA was maintained at an almost constant level by host plant cells from generation to generation. The high-efficiency transmission of the endogenous dsRNA to progeny plants appears to depend on the autonomously controlled replication of the dsRNA localized in cytoplasmic vesicles. However, an increase in copy number (about 10-fold) of the dsRNA was observed during the suspension culture of host cells. The number of copies of dsRNA returned to the original low value in regenerated plants, suggesting that the copy number is stringently and developmentally regulated in rice cells.
在健康的粳稻植株中发现了极少量的高分子量双链RNA（dsRNA）。我们区分了携带dsRNA的水稻植株和不携带的植株。内源性dsRNA定位于细胞质中（每个细胞约100个拷贝），并可通过交配传递给子代植株。在携带dsRNA的植株与不携带的植株杂交时，该RNA通过卵细胞和花粉高效传递给F1植株。水稻dsRNA在宿主植物细胞中代代维持在几乎恒定的水平。内源性dsRNA向子代植株的高效传递似乎取决于定位于细胞质小泡中的dsRNA的自主控制复制。然而，在宿主细胞的悬浮培养过程中观察到dsRNA的拷贝数增加了（约10倍）。在再生植株中，dsRNA的拷贝数恢复到原来的低值，这表明在水稻细胞中拷贝数受到严格的发育调控。
