Studies On BeSUSs Gene Expression Patterns Of Bambusa Emeiensis And Their Genetic Transformation In Populus Tomentosa

In this paper,BeSUS6 and BeSUS7 genes were cloned.The bioinformatics,expression patterns and subcellular localization of BeSUSs genes were analyzed.The overexpression vector of BeSUSs were constructed and transformed into Populus tomentosa.The results provide a foundation for the further studies to gain a systematic and comprehensive understanding of the SUS genes in regulating the bamboo plant growth.The results are as follows:1.Based on the full length sequences of five BeSUSs gene(BeSUS1-5)in the laboratory,two new BeSUSs were cloned and named as BeSUS6 and BeSUS7.The full-length cDNA sequence of BeSUS6 and BeSUS7 were 2526bp and 2550bp,which encoded 841 and 849 amino acids,respectively.Their registration numbers in GenBank are KY421768 and KY421769,respectively.2.The results of the expression pattern by Real-Time PCR showed that BeSUSs genes constitutively expressed,and the transcrpits of these BeSUSs were presented at different expression levels in all tissues examined and showed distinct but partially overlapping expression patterns.The expression of BeSUS3 were highest in root,stem,unexpanded leave and shoot.BeSUS1 and BeSUS7 genes were low in all tissues.And BeSUS6 gene was highest in expanded leaves.3.BeSUSs response to ABA,MEJA and drought treatment had also been investigated in leaves.The results showed that the up-regulated expression of the BeSUS4/5/7 genes and BeSUS1/5/7 genes and BeSUS6/7 genes were significant,induced by ABA,MEJA and drought treatment,respectively.Especially,BeSUS7 gene responded simultaneously to ABA,MEJA and drought treatment.4.The results of the expression of BeSUSs genes in the different tissues of shoot showed that BeSUS3,BeSUS4 and BeSUS5 had important effects on the growth and development of shoot.5.The Subcellular localization results showed that BeSUS2 Located on the cell membrane,while BeSUS4 was expressed in the cytoplasm and cell membrane.6.The overexpression vectors of BeSUS2/4/5/6/7 gene were constructed,and transformed into P.tomentosa by using Agrobacterium-mediated method.We obtained several transgenic plants of BeSUSs(11,11,14 and 13 transgenic plants of BeSUS2/4/5/6,respectively).The semi-quantitative PCR results showed that BeSUS2/4/5/6 was integrated into the genome of P.tomentosa and successfully expressed.7.The photosynthetic pigment content and stem diameter of the transgenic P.tomentosa in BeSUS2 were reduced abviously compared with the control,but the plant height was increased.