东方百合LoAS1和LoAS2基因的克隆、亚细胞定位及表达分析OA

AS1 and AS2 genes play critical roles in plant leaf development,however,whether LoAS1 and LoAS2 of Lilium Oriental Hybrids play a regulatory role during bulb low-temperature dormancy has not been reported.In order to investigate the correlation between LoAS1 and LoAS2 and the development of lateral primordia during bulb low-temperature dormancy,this study obtained the Lilium oriental'Sorbonne'MYB transcription factor LoAS1 and the LBD family gene LoAS2 by homologous cloning,constructed a phylogenetic tree,and analyzed their expression characteristics by RT-qPCR and subcellular localization.The results were as follows:(1)The coding sequence length of LoAS1 was 1 035 bp,encoding a total of 344 amino acids,while the coding sequence length of LoAS2 was 717 bp,encoding a total of 238 amino acids.(2)Phylogenetic analysis revealed that LoAS1 was more closely related to homologous proteins in Amana edulis and Lilium lancifolium,and most distantly related to Arabidopsis thaliana,Oryza sativa and Zea mays;LoAS2 was more closely related to homologous proteins in Elaeis guineensis and Cocos nucifera,and more distantly related to Oryza sativa and Zea mays.(3)Conserved motifs and structural domains analysis revealed that LoAS1 and LoAS2 share conserved motifs and N-terminal domains with their homologous proteins in other plants.(4)The results of subcellular localization revealed that LoAS1 protein was localized in the nucleus and LoAS2 protein in the cytoplasm and nucleus.(5)The overall expression levels of LoAS1 and LoAS2 were significantly higher than those in the normal temperature group,and both of them were up-regulated in the stem apex in response to the low-temperature,with their expression peaking at 30-40 d of storage.(6)The results of paraffin sections revealed that the lateral primordia of lily bulbs were significantly enlarged at 45 d of low-temperature storage,which was consistent with the expression patterns of LoAS1 and LoAS2.The study indicates that LoAS1 and LoAS2 may play an important role in the development of lateral primordia during the dormancy release process of lily bulbs,which provides a molecular basis for further research into the dormancy release mechanism of lily bulbs.