A PIP-family protein is required for biosynthesis of tobacco alkaloids |
| |
Authors: | Masataka?Kajikawa Nobuhiro?Hirai Email author" target="_blank">Takashi?HashimotoEmail author |
| |
Institution: | (1) Graduate School of Biological Sciences, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma Nara, 630-0192, Japan;(2) Graduate School of Agriculture, Kyoto University, 8916-5 Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto Kyoto, 606-8502, Japan |
| |
Abstract: | Plants in the Nicotiana genus produce nicotine and related pyridine alkaloids as a part of their chemical defense against insect herbivores. These
alkaloids are formed by condensation of a derivative of nicotinic acid, but the enzyme(s) involved in the final condensation
step remains elusive. In Nicotiana tabacum, an orphan reductase A622 and its close homolog A622L are coordinately expressed in the root, upregulated by methyl jasmonate treatment, and controlled by the NIC regulatory loci specific to the biosynthesis of tobacco alkaloids. Conditional suppression of A622 and A622L by RNA interference inhibited cell growth, severely decreased the formation of all tobacco alkaloids, and concomitantly induced
an accumulation of nicotinic acid β-N-glucoside, a probable detoxification metabolite of nicotinic acid, in both hairy roots and methyl jasmonate-elicited cultured
cells of tobacco. N-methylpyrrolinium cation, a precursor of the pyrrolidine moiety of nicotine, also accumulated in the A622(L)-knockdown hairy roots. We propose that the tobacco A622-like reductases of the PIP family are involved in either the formation
of a nicotinic acid-derived precursor or the final condensation reaction of tobacco alkaloids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. |
| |
Keywords: | Nicotiana tabacum Nicotine Nicotinic acid N-methylpyrrolinium cation PIP-family reductase |
本文献已被 SpringerLink 等数据库收录! |
|