SEPALLATA(SEP)1/2-like转录因子MdMADS9在早生富士苹果果实β-胡萝卜素合成中的作用

Effect of SEPALLATA(SEP)1/2-like Genes MdMADS9 on β-carotene Synthesis in Fuji Apple

β-胡萝卜素是苹果果实中重要的色素之一,具有较强的抗氧化能力。为了探索‘富士’苹果不同品系果肉类胡萝卜素含量差异的分子机理,利用同源克隆的方法从类胡萝卜素含量高的早生富士‘红将军’苹果果实中克隆出MADS9的同源基因MdMADS9。MdMADS9的开放阅读框为741bp,编码247个氨基酸。qRT-PCR分析表明,MdMADS9在‘红将军’果实不同发育时期果肉中的表达量高于对照‘Kiku’富士,而在果皮中‘Kiku’富士在前期的表达较高。qRT-PCR及SPSS显著相关性分析结果表明,MdMADS9与类胡萝卜素合成转化中的β-胡萝卜素羟化酶基因(CRH-β)相关。认为MdMADS9在苹果果实β-胡萝卜素的的合成中起调节作用。

β-carotene is one of the most important pigments in apple fruits,and it has strong antioxidant activities.In order to explore the molecular mechanism on the difference in carotenoid contents of fruit flesh among various strains of Fuji apple,MdMADS9 was isolated from early mature Fuji with yellow flesh using homology-based cloning method.MdMADS9 cDNA ORF is 741bp and encodes a 247 amino acid protein.qRT-PCR analysis showed that the expression level of MdMADS9 in early mature Fuji fruit flesh was higher than in Kiku Fuji,while the MdMADS9 transcription was more in Kiku skin than early mature Fuji in early fruit development periods.qRT-PCR and SPSS statistics analysis results indicated that MdMADS9 may have influence on β-carotene synthesis by controlling the expression of CRH-β.It is postulated that MdMADS9 may regulate the synthesis of carotenoids in apple fruit.