Abstract:

A cDNA fragment encoding ETR2-type ethylene receptor was isolated from partial-red fruits of ‘Dongzao’jujube with 3' RACE technique using degenerate primers corresponding for the conserved nucleotide and amino acid region sequences of the ETR2 family. The 5' encoding sequences of the cDNA were obtained by RT-PCR technique. The cDNA, named as ZjETR 2, contains a predicted 2 289 bp ORF(Open Reading Frame)encoding a 763 aa protein with 288 bp 3'UTR(Untranslated Region). The accession numbers in GenBank is DQ834687. ZjETR2 showed high similarity with ETR2-type ethylene receptor members from other plants at both nucleotide and amino acid level. Northern blot analysis indicated that ZjETR 2 transcription in jujube leaves was undetectable, and expressions of ZjETR 2 in young jujube fruits were very low, whereas expressions at the ripening stages of jujube fruits obviously increased.

Key words: Ziziphus jujuba &lsquo, Dongzao&rsquo, fruit ripening, ethylene receptor, cloning, expression