Molecular characteristics and promoter analysis of SlLCY-B2 gene in tomato

【Objective】 Lycopene synthesis can enter the metabolic pathway catalyzed by lycopene-β-cyclase sllcy-B, and inhibition of the expression of SlLCY-B2 can increase the accumulation of lycopene. The molecular characteristics and sgRNA of lycopene metabolism regulation gene SlLCY-B1 were systematically analyzed in order to utilize CRISPR/ Cas9 Site-directed mutation or fragment deletion of SlLCY-B2 and its upstream promoter sequences was performed to regulate the expression of SlLCY-B2 and reduce metabolic pathways to improve the content of lycopene in tomato fruits. 【Methods】 The characteristics, conserved domain, genome structure, digital expression profile and promoter cis-acting elements of SlLCY-B2 polypeptide were systematically analyzed by online biological tools. According to the design principle of CRISPR-Cas9 target, suitable sgRNA was designed and screened out. 【Results】 SlLCY-B2 was located on chromosome 6 of tomato and encodes 498 amino acids. The gDNA did not contain introns and was specifically expressed in fruit. SlLCY-B2 distributed 145 Sgrnas, of which 21 were highly specific. There were 15 cis-acting elements and 112 Sgrnas in the 1 500 bp promoter sequence upstream of SlLCY-B2. 【Conclusion】 l Gene editing of SlLCY-B2 and its promoter region can regulate the expression of SlLCY-B2 and increase lycopene content.