The Regulation Role Of ANS、ANR And LAR Gene In Strawberry Anthocyanin Biosynthesis Pathways

Fragaria×ananassa, commonly known as strawberry, is a hybrid species that belonges to the Rosacea family, Fragaria genera. Its fruits is widely appreciated by consumers worldwide for its bright red color, juicy texture, characteristic aroma, and sweetness. The tremendous amount of anthocyanins in strawberry fruit attributed not only the lovely color, but also bring us multiple bio-physiological functions, participating in radical scavenging, oxidative enzyme degradation, immune system enhancing likewise. When applied in medical or nutrimental areas, it has capability in anti-mutation, anti-tumor, ease-allergy and many other useful healthy promoting functions. Moreover, anthocyanin is a natural dye exhibited colorful appearance in both production and food industries with increasing economic values. On the other hand, as an internal secondary metabolic compounds in plants, anthocyanin play an important role in responding to the environmental stress or normal physiological process. For instances, anthocyanin could bring to attraction for animal predator feeding for seeds dispersal, or protection the plants from UV light injuries. In this manuscript, the commonly used excellent strawberry cultivar’fengxiang’(Fragaria x ananassa cv. Toyonaka) was used to investigate the expression patterns of three genes:FaANS, FaANR and FaLAR, which was either involved in anthocyanin biosynthesis or imparted in the proanthocyanidin accumulation. Meanwhile, the quantitative content of both products in varies maturation stages of the fruits were determined. Combined these results, functions of the genes were confirmed by simple correlation analysis. The major findings were presented as follows:1. Total RNA of high quality was isolated from strawberry fruits at different maturation stage using the modified CTAB method.2. The total concentration of anthocyanins was assayed by the pH differential assay from strawberry fruits at different maturation stage, proanthocyanidins was determined using a standard method based on the specificity reaction between flvanol and DMACA reagent. The results indicated that the anthocyanins was riched in the strawberry fruits maturation(18.61mg/g FW). The content was lowest in the early green fruits, and then gradually increased along with the fruit maturation. But the concentration of PAs was highest(26.27mg·g-1FW)in the early green fruits. The concentration of PAs was gradually reduced as the strawberry fruits maturation, and the concentration of PAs was lowest at the fruit maturation.3. The expression levels of FaANS, FaANR and FaLAR gene at seven maturation stages of strawberry fruits were determined by RT-qPCR, and combined with the total contentration of the anthocyanins and PAs,and analyzed the correlation between them. The results indicated that the expression patterns of FaANS were consistent with the anthocyanins from the strawberry fruits, and they have a similar pattern:increased as the fruits maturation. from SG to FR, total anthocyanins concentration gradually accumulated, transcript levels of Fa-ANS gradually also increased. The expression level of the FaANS was lowest in the early green fruits (SG), gradually increased to the maximum at the fruits maturation (FR). The expression level of the FaANR and FaLAR was highest at the small green stage (SG), and gradually decreased to the minimum at the full red stage (FR). The pattern was consisting with that PAs was found in strawberry fruit.