甘蓝BoSVP mRNA运输鉴定及其对砧木SVP转录表达的影响

Identification of mRNA Transport of BoSVP in Grafted Cabbage and It′s Effect on Transcription Expression of SVP in Rootstocks

为明确SVP mRNA运输特点,探讨mRNA运输机制,本研究构建了甘蓝/菜心嫁接体,对嫁接体的砧木菜心和菜心实生苗(对照组)的花序轴进行转录组测序。使用菜心种间差异序列(C1-C9)在砧木菜心转录组测序文库中进行检索,比较相邻两个种间差异序列的检索数值,显示使用C7和C8检索所获得的数值之间的偏差最小,适合于评估mRNA运输。利用甘蓝种间差异序列G7和G8,在砧木菜心花序轴的转录组测序文库中共检索到11条read,将其与BoSVP和BrSVP进行比对,显示这些read均来源于BoSVP,证实了甘蓝BoSVP的mRNA可从接穗甘蓝运输到砧木菜心中。通过比较砧木菜心文库中甘蓝BoSVP和菜心BrSVP的read数量,显示外源的BoSVP read数量远小于内源的BrSVP read数量。比较嫁接体菜心和菜心实生苗花序轴中SVP基因的转录表达,两者差异不显著,说明BoSVP的mRNA运输几乎不影响砧木菜心花序轴中SVP的转录表达。本研究鉴定了甘蓝BoSVP基因的mRNA运输,分析了接穗甘蓝的BoSVP mRNA运输对砧木菜心花序轴中SVP转录表达的影响,为进一步研究嫁接体中甘蓝BoSVP基因的mRNA运输功能奠定了基础。

To clarify the characteristics of mRNA transport of SVP and investigate the mechanism of mRNA transport, head cabbage/Caixin heterograft was constructed in this study. Inflorescence stems from the heterografts and the ungrafted seedlings of Caixin(the control) were performed with transcriptome sequencing. The nine interspecific differential sequences of Caixin(C1-C9) were used for searching in the transcriptome sequencing library of inflorescence stems of the heterografts. Analysis of retrieval value of two adjacent interspecific differential sequences indicated that C7 and C8 had the least deviation and were suitable for the evaluation of mRNA transport. A total of 11 reads were retrieved from the transcriptome sequencing library of the heterografts with G7 and G8. When compared with BoSVP and BrSVP, all reads were originated from BoSVP, confirming that the BoSVP mRNA could be transported from scion to rootstock. The comparison between read number of exogenous BoSVP and endogenous BrSVP in transcriptome sequencing library of the heterografts indicated that the read number of exogenous BoSVP was much less than that of endogenous BrSVP. There was no significant difference in the SVP expression between the inflorescence stems of heterografts and the ungrafted seedlings, indicating that mRNA transport of BoSVP hardly affected the transcriptional expression of SVP in inflorescence stems. In this study, mRNA transport of BoSVP was identified and the effect of BoSVP mRNA transport on the transcriptional expression of SVP in the inflorescence stems of heterografts was analyzed. This study lays a foundation for further study on the function of BoSVP mRNA transport in the heterografts.