Cloning And Functional Analysis Of LsCCR1 And Ls4CL Genes Related With Lignin Synthesis In Lilium Oriental Hybrids

In this study, we compared the variation on cell structure and lignin content between"Sorbonne"and"Siberia"during the stem development, growth and flowering, which are very fashion and with excellent records on the flower marketing. Then a Cinnamoyl-CoA reductase (CCR) gene and a 4-Coumarate: CoA ligase (4CL) gene, which were the key genes in the pathway of the lignin synthesis, had been cloned from Lilium oriental hybrids"Sorbonne"plants by RLM-RACE. These genes were been named as LsCCR1 and Ls4CL respectively. The main results are as follows:1. There were differences to be found on quick accumulation period and rate of stem lignin contents between"Sorbonne"and"Siberia". At later growth stage, lignin contents both at the up part and lower part of"Sorbonne"stem was higher than those of on Siberia's. Nevertheless, there were much significant differences in lignin content at the lower part of the stem between two varieties.2. The LsCCR1 cloned is a 1499bp full-length cDNA with whole ORF encoding 388 amino acids. The expression of LsCCR1 in different tissues of lily was detected by a semi-quantitative RT-PCR. The LsCCR1 predominantly expressed in the stem and root tissues, and at low expressed in leaf, bulb scale and flower bud The results of real time PCR analyses showed that the expressions level of LsCCR1 at the under lignifying upper part of stems obviously higher than that of lignified lower part of stem. There might be a much higher expressions of LsCCR1 RNA in the up part of stem with prosperous growth vigor on"Sorbonne". At various growth periods, the LsCCR1 expression levels were different between two varieties also.3. The functional analysis of the cloned genes through transgenic tobacco showed that the expression levels of LsCCR1 have great difference among 11 detected lines by semi-quantitative RT-PCR. Transgenic phenotypes with over-expressing 35::LsCCR1 make a great difference, especially on plant height. Some lines have variation in flower morphology and flower color. Moreover the structure and number of xylem cell on transgenic tobacco have also varied.4. The Ls4CL is a 1966bp full-length cDNA with whole ORF encoding 548 amino acids. The expression of Ls4CL in different tissues of lily was detected by semi-quantitative RT-PCR. The Ls4CL was mainly expressed in stem and root, and at low expressed relatively in leaf, bulb scale and flower bud.