我们用[~3H]—Poly(U)饱和杂交的方法分析了水稻种子发育过程中Poly(A)含量和Poly(A)RNA水平的变化。胚乳发育过程中,Poly(A)含量和Poly(A)RNA水平均于开花后11天达到高峰,比蛋白质高峰出现时间约早10天。随着胚乳的成熟,蛋白质水平在开花后6～21天持续增长。但 Poly(A)含量和Poly(A)RNA水平却急剧下降。因此,在胚乳发育早期合成的Poly(A)RNA中,可能有部分不是直接用于蛋白质的合成。在胚的发育过程中,Poly(A)含量和Poly(A)RNA水平分别出现三次高峰。开花后30天,每胚含有5.94ng Poly(A)RNA,约占胚总RNA的0.097％,为稻胚中贮存的mRNA存在提供了一个直接的证据。 We analyzed the changes of poly (A) content and Poly (A) RNA level during rice seed development by [~ 3H] -Poly (U) saturation hybridization. During endosperm development, the content of Poly (A) and the level of Poly (A) RNA all reached the peak 11 days after flowering, which occurred about 10 days earlier than the peak of protein. As endosperm matures, protein levels continue to grow 6 to 21 days after flowering. However, the levels of Poly (A) and Poly (A) RNA dramatically declined. Therefore, some of Poly (A) RNA synthesized early in endosperm development may not be directly used for protein synthesis. Poly (A) content and Poly (A) RNA levels peaked three times during embryonic development. At 30 days after flowering, each embryo contained 5.94 ng of Poly (A) RNA, accounting for 0.097% of total embryonic RNA, providing a direct evidence of the presence of mRNA stored in rice embryos.