the authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest .
flowering locus t ( ft ) protein is known to be part of the mobile flowering inducing  florigen  signal in plants , but it may not be acting alone . 
 this article reviews the data that ft mrna can also move systemically throughout the plant and into the shoot apical meristem ( sam ) independently of the ft protein . 
 there is a promotion of flowering when increased levels of virally expressed ft mrna are present together with endogenously produced ft protein in inducing conditions , even if the additional ft mrna is non - translatable and thus not increasing the overall levels of ft protein . 
 a specific sequence , or  zip code  of the ft mrna is required for systemic movement and this sequence binds a specific protein(s ) in plant extracts . 
 this raises the possibility the ft mrna may be moving systemically through the plant and into the sam as an rna  protein complex , whether ft protein is also a component of this mobile complex remains to be determined .