Abstract: The florigen gene which designated as AcFT isolated from the leaf of Allium cepa line，
‘1007’from vernalization period to bolting period（GenBank accession No. KF913629）. The full-length
cDNA of florigen gene in A. cepa was obtained by RT-PCR and Rapid Amplification of cDNA Ends. The
cDNA sequence of AcFT was 791 bp long and the open reading frame was 534 bp long which could
encode a putative protein of 177 amino acids with a molecular weight of 19.8 kD and a theoretical pI of
7.89. Compared and analyzed the amino acid sequence of florigen gene with Allium fistulosum，Iris fulva
and so on，the A. cepa shared over 65% nucleotide sequence similarity with others and the similarity of
amino acids with the florigen gene in A. fistulosum is 98.31%. Fluorescence quantitative RT-PCR system
followed was established to examine the expression of AcFT. As a result，the AcFT gene from A. cepa
detected during th e different tissues that was root leaf sheath，leaf，stem and inflorescence from bolting to
vernalization，and it was highly expressed in leaves before bolting after vernalization.

Key words: Allium cepa, AcFT gene, RACEPCR, fluorescence quantitative, expression analysis