Correlation Of HY5 And GRAS Transcriptional Factors To Low Temperature Tolerance Of Lepidium Apetalum

In this paper,the Lepidium apetalum which lives in the north of Xinjiang,belongs to the early spring ephemeral plants of the family cruciferous,and plays an important role in the flora of Xinjiang.It is found that there is a low temperature stagnation phenomenon in the germination and elongation of the hypocotyl of the seeds of plateaus Lour.If the higher temperature stimulus is given during the low temperature stagnation period,the hypocotyl elongation and stagnation phenomenon can be relieved.The Lepidium seeds of low temperature-tolerant in germination period were set as experimental group(D),and the seeds of in stagnating germination period under low temperature were set as the control group(CK),and then the transcriptome of the Lepidium seeds were sequenced.Analysis of sequencing results showed that the expression level of HY5 transcription factors changed significantly before and after the hypocotyl germination and stagnation of the seeds of Lepidium.So a lot of experiments were done on the gene and the following results were obtained: 1.The results of the study on the HY5 gene of Lepidium:(1)After analyzing the transcriptome data of the seeds of Lepidium,we screened 5 HY5 genes with significant difference in the experimental group compared with the control group,and verified their expression characteristics,which is consistent with the data in the transcriptome database.(2)A gene with the most significant difference in expression was selected from 5 HY5 genes,and the gene was cloned to obtain a full length of LaHY5.The fluorescence quantitative analysis showed that the expression of the gene was related to the temperature,and there was a difference in the expression of the gene in the growth and development of the Lepidium.(3)The plant expression vector pMON530-LaHY5 was constructed and transformed into Agrobacterium by electric shock,and the Arabidopsis thaliana was transformed by the method of dipping.The T1 hypothermia tolerance of transgenic Arabidopsis thaliana was significantly higher than that of wild Arabidopsis thaliana,indicating that LaHY5 gene played a role in temperature regulation of the hypocotyl elongation of the seeds of Lepidium.2.The results of the study on the GRAS gene of Lepidium:(1)In this study,the GRAS transcriptional factors were analyzed.It was found that there were 270 members of the GRAS family in the Lepidium seed transcriptional group.138 members were up-regulated compared with the low temperature germination stagnation group,and they were up-regulated in the low temperature germination of the seeds of Lepidium,128 down regulated expression,and 4 expression levels were not different.(2)One of the most significant up-regulated expression GRAS genes was cloned and a full-length gene LaGRAS was obtained.Fluorescence quantitative analysis showed that the expression of LaSCL18 gene increased rapidly after processing under low temperature stress.It was preliminarily speculated that the expression of LaSCL18 gene was related to the low temperature tolerance of the seedlings of Lepidium.To sum up,the LaHY5 gene regulates the hypothermia elongation of the Hypocotyl in the single course,and the LaSCL18 gene can improve the low temperature tolerance of the seedlings of solo solo.The above results provide a new way of thinking for the study of the germination characteristics of the early spring short life plants in Xinjiang.