【摘要】 根据乙烯受体基因的保守序列设计引物 ,分别从荔枝、香蕉、木瓜、芒果和莲雾等五种热带水果的基因组DNA中克隆出的乙烯受体基因的保守序列 ,序列长度分别为 14 4 0bp、 14 4 1bp、 14 39bp、 14 4 0bp和 14 4 0bp ,序列分析表明 ,与栽培稻的ers基因相似性最高。五种热带水果乙烯受体基因保守序列存在明显的单核苷酸变异 ,在 19个核苷酸位点存在SNPs (singlenucleotidepolymorphisms) ,其中 12个SNPs存在于内含子中 ,7个SNPs存在于编码序列区。在编码序列区的SNPs ,荔枝与其他 4种热带水果相比具有较高的单核苷酸多态性 ,荔枝有 4个核苷酸的变异 ,其余 4种热带水果仅有一个核苷酸变异。编码区序列中的单核苷酸的改变 ,除了第 783位核苷酸的不同没有引起氨基酸改变外 ,其余均导致编码氨基酸的改变更多还原

【Abstract】 The universal primer for amplifying conserved sequences of the ethylene receptor genes of five tropical fruits have been designed based on registered ethylene receptor genes (ers) in GenBank. The length of the conserved sequence from lytchee(Litch chinensis), mango(Mangifera indica) and wax apple(Syzygium samarangense) are 1440bp, and that from banana(Musa AAA Group) and papaya(Carica papaya) are 1441bp and 1439bp, respectively. Sequence analysis shows that these fragments have the 99% identities with the sequence of ethylene receptor gene (ers) of rice (Oryza Sativa), and 88% identities with that of maize (Zea mays). The sequence length polymorphism exits in one or two base pairs in obtained sequences. Each conserved sequence has 2 introns by comparing with the sequences registered in GenBank, the length of intron II is the same of 94bp in all tested tropical fruits. There are 2bp difference in intron I of banana and papaya, which the length is 373bp and 371bp, respectively. There are no difference in intron I of lytchee, mango and wax apple, which the length is 372bp. The single nucleotide variations were found in the conserved sequences of five tested tropic fruits. There are 19 SNPs (single nucleotide polymorphisms) in the obtained sequence, 12 SNPs of them in the introns, 7 SNPs of them in the encoding region. Lytchee has 4 SNPs in the encoding region more than that of others. The variation of SNPs in encoding region results in the changes of amino acids except the SNP site No.783.更多还原