Abstract
Arabidopsis FLOWERING LOCUS T (FT) is expressed in leaves in response to inductive long days and FT protein acts in the shoot apex to promote flowering. Recent studies have provided evidence that the FT protein is an important part of florigen. However, there still are issues to which we adopt different approach. Main points in our experiments: 1) long-distance transport was detected by using micrografting technique in Arabidopsis; 2) T7 tag was chosen for the detection of FT protein, other than GFP tag which itself have ability for long-distance transport via phloem; 3) we investigated the temporal aspects and suggested that FT protein transport occurred within 24-48 hr; 4) the sequence and structure of mRNA are not of critical importance for the long-distance action of the FT gene. These observations led to the conclusion that the FT protein, but not mRNA, is the essential component of florigen.
