酿酒酵母菌核糖体RNA沉降系数的初步研究

为研究酿酒酵母菌核糖体RNA(rRNA)的沉降系数,用酶解法和液氮研磨法裂解酿酒酵母菌的细胞壁,Trizol Reagent提取其总RNA,同时提取小白鼠和斑马鱼的总RNA进行比较.经紫外分光光度计检测和甲醛琼脂糖变性胶电泳后,RNA纯度好,条带清晰,无弥散或降解现象.试验发现,与酶解法相比,用液氮研磨法破碎酿酒酵母菌细胞壁提取总RNA所用的成本低,时间少,产率和纯度高,适用于少量样品RNA的提取.同时,酿酒酵母菌与斑马鱼和小白鼠总RNA电泳图谱表明,三者的"18S rRNA"在条带大小方面差异较小,而"28S rRNA"差异较大.利用分析型离心机测得的酿酒酵母菌两个较大rRNA的沉降系数分别为24.7S和18.1S.研究结果表明了真核生物rRNA种类的多样性.

Study on the Sedimentation Coefficient of Ribosomal RNA from Saccharomyces cerevisiae

To study the sedimentation coefficient of ribosomal RNA from Saccharomyces cerevisiae,the enzymolysis method and the liquid nitrogen grounding method combined with Trizol Reagent were used for total RNA extraction from Saccharomyces cerevisiae.RNA extraction in Mus musculus Kunming and Danio rerio,was also involved in,which was set as control.The RNA concentration and the A260/A280 ratio were measured by the ultraviolet spectrophotometer,and the RNA integrity was checked by formaldehyde denaturing gel.The A260/A280 ratio ranged between 1.8 and 2.1 indicating that the RNA is relatively pure.Fractionation by agarose gel electrophoresis revealed distinct bands,without obvious smearing or degradation.Compared with enzymolysis method,the liquid nitrogen grounding method is less expensive and less time-consuming,but gives higher yield and purity,and suitable for RNA isolation from small number of samples.The result of electrophoresis showed that "18S" bands of the three species are alike in size,while "28S" bands vary to some extent.Analytical ultra-centrifuge was used to calculate the sedimentation coefficient of the two larger rRNA from Saccharomyces cerevisiae,24.7S and 18.1S,respectively.These results showed the diversity of rRNA species among eukaryotic organisms.