title: Histochemical study of trans-polyisoprene accumulation by spectral confocal laser scanning microscopy and a specific dye showing fluorescence solvatochromism in the rubber-producing plant, Eucommia ulmoides Oliver.
abstract: A microscopic technique combining spectral confocal laser scanning microscopy with a lipophilic fluorescent dye, Nile red, which can emit trans-polyisoprene specific fluorescence, was developed, and unmixed images of synthesized trans-polyisoprene in situ in Eucommia ulmoides were successfully obtained. The images showed that trans-polyisoprene was initially synthesized as granules in non-articulated laticifers that changed shape to fibers during laticifer maturation. Non-articulated laticifers are developed from single laticiferous cells, which are differentiated from surrounding parenchyma cells in the cambium. Therefore, these observations suggested that trans-polyisoprene biosynthesis first started in laticifer cells as granules and then the granules accumulated and fused in the inner space of the laticifers over time. Finally, laticifers were filled with the synthesized trans-polyisoprene, which formed a fibrous structure fitting the laticifers shape. Both trans- and cis-polyisoprene are among the most important polymers naturally produced by plants, and this microscopic technique combined with histological study should provide useful information in the fields of plant histology, bioindustry and phytochemistry.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan. hitzbiolab@hitzbio.com
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Nakazawa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takeda
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Suzuki
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Hayashi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Harada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Bamba
authors.forename: Akio
authors.initials: A
authors.lastname: Kobayashi
mesh_terms: D031283:Eucommiaceae / Q000378:metabolism*; D005453:Fluorescence; D045782:Hemiterpenes / Q000378:metabolism*; D018613:Microscopy, Confocal / Q000379:methods*; D012408:Rubber / Q000378:metabolism*
chemical_list: D045782:Hemiterpenes; D012408:Rubber