Phenylalanine ammonia-lyase and chalcone synthase in glands of Primula kewensis (W. Wats): immunofluorescence and immunogold localization

Abstract

Abstract. Phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) were localized by indirect immunofluorescence and immunogold labeling in glands of Primula kewensis. Both enzymes were exclusively present in the head cells of the glands. Phenylalanine ammonialyase was located in the regions of the dense tubular endoplasmic reticulum and occasionally found in more or less spherical organelles that have not yet been identified. Furthermore, an appreciable proportion of the enzyme protein was associated with the plasmalemma and the cell wall of the head cell. In contrast, the occurrence of CHS was restricted to the spherical, unidentified cell compartments. Our findings indicate that the gland cells have the potential for flavonoid biosynthesis. When a mutant of P. kewensis forming structurally intact glands but incapable of farina excretion was studied, neither PAL nor CHS were found in the head cells.

Sub-cellular trafficking of phytochemicals explored using auto-fluorescent compounds in maize cells

“…Interestingly, a recent study on Arabidopsis roots determined that at least two flavonoid biosynthetic enzymes, chalcone synthase and chalcone flavanone isomerase, are localized in electron-dense bodies that resemble in size and localization the electron-dense structures observed here [24]. Similar vesicle-like structures have been also previously observed for the localization of a flavonol O -glucosyltransferase in Chrysosplenium americanum cells [25], and for Primula kewensis ' chalcone synthase [26]. These findings open the possibility that cytoplasmic structures resembling the electron-dense bodies described here function not only as the sites of storage or transport of specific phytochemicals, but also participate in specific steps in their synthesis, similar to what has been found for alkaloid vesicles [27].…”

Immunocytological localization of two enzymes involved in berberine biosynthesis

“…Therefore, few investigations of in situ localization of such enzymes have been successful (Beerhues et al 1988;Scho¨pker et al 1995). Our data demonstrate for the first time the in situ localization of two branchpoint enzymes of the secondary pathway in a specific and unique compartment.…”

Sporoderm development and substructure inMagnolia sieboldiiand other Magnoliaceae: an interpretation

“…We suppose that the plastid osmiophilic inclusions can be related to the synthesis of SP integral constituents. The smooth endoplasmic reticulum may play a significant role in the synthesis and transport of phenolic substances (Wagner & Hrazdina, 1984;Schopker et al, 1995;Muravnik, 2007). Enzymes of phenylpropanoid metabolism were found in Ǟ Figure 11.…”