Cloning and expression analysis of R1-MYB transcription factor in Lycium ruthenicum / 中草药

ABSTRACT

Objective To clone the R1-MYB transcription factor participated in the anthocyanidin metabolism, and to analyze by bioinformatics analysis. Different expression of different varieties, different organs of the same species and salt stress conditions in Lycium were analyzed. To clone the full-length cDNA encoding R1-MYB, to perform bioinformatic analysis, and to study its expression in different cultivators and different developmental stage and in response to NaCl stress in Lycium ruthenicum and L. barbarum. Methods The full-length cDNA encoding R1-MYB was cloned using homology-based cloning and rapid amplification of cDNA ends (RACE) technique in L. ruthenicum, and the homologous gene was obtained by transcriptome in L. barbarum. The bioinformatics analysis was carried out by using Prot, Param, Smart, PSORT, and SOPMA methods. And the phylogenetic tree was constructed based on software MEGA5.0. Gene expression analysis was done by method of Real-time PCR. Results We the MYB transcription factor in L. ruthenicum was cloned and named as LrMYB1R1 (GenBank accession number KY568981), and LbMYB1R1 (GenBank accession number KY568982) in L. barbarum. Bioinformatics analysis showed that the length of LrMYB1R1 was 1 496 bp and the CDS was 927 bp. The coding products contained 308 amino acids, the molecular weight of the protein was 33 400 and 33 490, the theoretical isoelectric point was 7.80 and 7.78, belonging to the R1-MYB transcription factor, and the encoded protein is predicted to be located in the nucleus. The results of phylogenetic tree analysis showed that LrMYB1R1 and LbMYB1R1 were highly similar to MYB1R1-like protein in Solanum lycopersicum, Solanum tuberosum, and Nicotiana tabacum. Real-time PCR analysis showed that LrMYB1R1 had higher expression level in leaves and young fruits in L. ruthenicum, followed by stems, young leaves, flowers, purple fruits and black fruits, only slightly expressed in roots. In addition, the relative expression levels of LrMYB1R1 decreased in response to salt stress. Conclusion The study of R1 MYB transcription factor has been enriched, which has laid the foundation for the subsequent research on gene function and for the high-yielding anthocyanin by genetic engineering method in L. ruthenicum.