Research On SUT And SWEET During The Development Of LA Hybrids Lily Bulbs

The quality of lily cut flowers was determined by the quality of bulbs.It was essential to study the molecular regulation mechanism for the lily bulbs development.Sugar was massively accumulated during vernalization and flower bud differentiation and would influence the whole process of lily bulb development.However the details of sugar genes regulation mechanism for these processes were unclear.So it was important to annotate more sugar genes and study the function of sugar genes during vernalization and flower regulation of lily.That would be beneficial to our lily industry.In this paper,we explored the glucose metabolism pathway during the development of Lilium longiflorum ×Asiatic 'Aladdin' bulbs by physiological and morphological study,transcriptomics and molecular biology.Here are the conclusions:(1)The transcriptome sequencing data of Asian lily 'Tinny ghost' bulbs was re-analysed,which was generated on Hiseq Illumina 2000.The results showed that the these sugar related genes were closely related to lily bulb vernalization.Combining gene expression patterns during development and gene co.expression network,seven genes(Contig2592?Contig3309?Contig779?Contig13408?Contig3984?Contig2207?Contig 1397)were considered to be the most potential signals contributing to lily bulb vernalization and development.And according to that SUT was the focus of this paper.(2)The changes of sugar and hormones in lily scales and the expression trends of target genes in bulb growth points were obtained through physiological and qRT-PCR test for Lilium longiflorum x Asiatic 'Aladdin'.Soluble sugars,especially sucrose,peaked at the completion of vernalization,suggesting that it may be a key signal.The high ratio of ABA/GA3 and ZR/GA3 was beneficial to the flower buds of lily from growth to differentiation.SWEET was active during vernalization,and SUT peaked in flower bud differentiation.Both of them could sense and regulate sugar concentration,which might have effects on bulbs development.While the SUT gene may regulate the lily flowering stage.(3)LlaSUT2,LlaSUT4 and genes were cloned by RT-PCR,which were the first time for Lilium longiflorum × Asiatic.The physiological properties of these proteins were analyzed.And secondary and third structure of proteins were predicted,which indicated the three proteins were membrane protein.Their cellular locations were verified through positioning experiment of fluorescent vector,which illustrated the key role for these genes in sugar transport.