One of the highlights of the month of July in Japan is Tanabata (Star Festival). Tanabata, a festival to pray to the stars in the Milky Way in summer, was imported from ancient China. People in Edo era started to decorate bamboo branches with ‘tanzaku’ (small pieces of paper) on which they wrote their wishes, and to pray the wishes would come true. The bamboo branches in this drawing are likened to histone tails (H2A, H2B, H4 and H3 from the left). The tanzakus represent epigenetic modifi cations (acetylation, methylation and phosphorylation) of amino acid residues in histone tails. If you use this histone bamboo, mind that you have to phrase your wishes with the types, positions and combinations of decorations (or modifications). You need a textbook to perform modifi cations correctly.
It was in 1936 when the existence of ‘florigen’ was initially predicted as a plant hormone that transmits information on daylight length at their leaves to the tip of the stem and stimulates flower initiation. In 2007, it was finally identified as a protein, which is coded by the FT gene in Arabidopsis thaliana. FT protein is produced in the leaves and transmitted to the growing tip at the shoot apical meristem via the phloem, and interacts with a transcription factor (the product of the FD gene in Arabidopsis) to induce genes involved in flower initiation. In this drawing, an actor performing FT is contacting another actor performing FD, and trying to stimulate flower initiation with him in front of hydrangea flowers that represent the month of June in Japan.