Isolation of PolyA-RNA from mycelium of N2-78 indu...
Since mRNA plays an important link in gene expression of cells，the change in mRNA content in mycelium during cellulase induction was determined.The content of RNA reached a maximum after 6 h induction（see Figure 8）.The total RNA was extracted with phenol for 6 h at low temperature（＜5℃）from 100 ml of washed mycelium which had been incubated with sophorose.RNase was inhibited by diethylcarbonate.Total RNA was then separated into three peaks（Ⅰ，Ⅱ and Ⅲ）by oligo（dT）-cellulose affinity chromato graphy（see Figure 10）.The A260/A280 ratios of peaks Ⅰ，Ⅱ and Ⅲ were 2.24，2.14 and 2.16，respectively.Peak I was rRNA，comprising 90%of the total RNA.Peak Ⅲ，the polyA-RNA，showed the typical UV absorption spectrum of RNA.It was eluted with Tris buffer at low ionic strength or by water.It is important to note that the content of polyA-RNA in mycelium induced by sophorose was higher than the control，as shown by affinity chromatography（see Figure 11）and polyacrylamide gel electrophoresis.［2］(https://www.daowen.com)
Figure 10 Chromatography of total RNA of mycelium of Trichoderma N2-78 induced by sophorose through oligo（dT）-cellulose column［9］A，0℃，0.01 MTris，pH=7.5，0.5 M KCl；B，54℃，0.01 M Tris，pH=7.5，0.5 M KCl；C，54℃，0.01 M Tris，pH=7.5(https://www.daowen.com)
