杨树miR393对FBL基因家族成员调控作用的鉴定

Identification of regulation of poplar miR393 on FBL family genes

【目的】揭示ptc-miR393对杨树FBL基因家族不同成员的剪切调控作用。【方法】首先将杨树FBL基因家族成员与双子叶植物、单子叶植物和蕨类植物代表物种拟南芥、水稻和小立碗藓的FBL基因家族成员进行系统进化分析;再对杨树FBL家族成员的基因结构进行比较;最后通过ptc-miR393与杨树FBL基因家族成员的序列比对、ptc-miR393及FBL基因家族成员在杨树不同发育时期及不同组织中的表达模式以及5′-RACE检测等方面对杨树miR393与FBL基因家族成员的调控作用进行鉴定。【结果】杨树FBL基因家族共有8个不同成员,两两成员之间的同源性较高,通过基因结构和功能域分析,表明它们之间可能存在冗余的功能;PtFBL1-PtFBL4之间具有较高的同源性,位于一个进化分支上,而PtFBL5、PtFBL6和PtFBL7、PtFBL8分别位于不同的分支且与PtFBL1-PtFBL4的同源关系较远。杨树FBL基因的结构和结构域出现一定的变化,预示着它们之间可能出现了分化,在时空调控上的作用有所改变。ptc-miR393与PtFBL1-PtFBL4的互补配对率较高,而与PtFBL5-PtFBL8之间有5~7个碱基的差异,在杨树不同发育时期及不同组织中,PtFBL1-PtFBL4的表达与ptc-miR393呈相反的趋势,而PtFBL5-PtFBL8的表达不受ptc-miR393的影响,5′-RACE实验也检测出PtFBL1-PtFBL4受ptc-miR393的剪切,而PtFBL5-PtFBL8不受ptc-miR393的剪切。【结论】PtFBL1、PtFBL2、PtFBL3和PtFBL4是ptc-miR393的靶基因,而PtFBL5、PtFBL6、PtFBL7和PtFBL8不受ptc-miR393的剪切调控,这为进一步揭示ptc-miR393对杨树FBL基因的调控功能奠定理论基础。

【Objective】To reveal the regulation of poplar miR393 on different members of FBL gene family.【Method】Firstly, the phylogenetic evolution of poplar FBL gene family members were analyzed with the FBL gene family of Arabidopsis thaliana, Oryza sativa and Physcomitrella patens, which are the representative species of dicotyledons, monocotyledons and ferns respect. Then, the gene structures of poplar FBL gene family members were compared. Finally, the sequence alignment between ptc-miR393 and FBL genes, the tissue expression patterns of ptc-miR393 and FBL genes and 5′-RACE validation were analyzed in this work to identify the regulatory role of miR393 and FBL genes in poplar.【Result】There are eight different members in poplar FBL gene family, and the homology between two members is high. The analysis of gene structure and functional domain indicates that these genes have redundant functions between them. PtFBL1-PtFBL4 have high homology, which are clustered in one evolutionary branch, while PtFBL5, 6 and PtFBL7, 8 are located in different branches and have far homology with PtFBL1-PtFBL4. The gene structures and domain structures of FBL genes in poplar have changed, which indicates the change of temporal and spatial regulation. ptc-miR393 has higher complementary pairing rate with PtFBL1-PtFBL4, but has 5-7 bases difference with PtFBL5-Pt FBL8. In different developmental stages and tissues of poplar, the expression of PtFBL1-PtFBL4 is opposite to that of ptc-miR393, while the expression of PtFBL5-PtFBL8 is not affected by ptc-miR393. 5′-RACE detection show that PtFBL1-PtFBL4 arecleaved by ptc-miR393, while PtFBL5-PtFBL8 are not cleaved by ptc-miR393.【Conclusion】This workdemonstrates that PtFBL1, PtFBL2, PtFBL3 and PtFBL4 are the target genes of ptc-miR393, while PtFBL5, PtFBL6, PtFBL7 and PtFBL8 are not regulated by ptc-miR393, which makes a foundation for further study in revealing the regulatory function of ptc-miR393 on poplar FBL genes.