title: Seasonal-based temporal changes fluctuate expression patterns of TXS, DBAT, BAPT and DBTNBT genes alongside production of associated taxanes in Taxus baccata.
abstract: Environmental cues have synergistic or antagonistic regulatory roles on transcription activity and taxanes accumulation in yew, though DBAT activity is less influenced, could be accordingly a rate-limiting enzyme. The current work was undertaken to elucidate the consequences of some environmental cues (i.e., day length, temperature, sunlight and relative humidity) on the expression patterns of TXS, DBAT, BAPT and DBTNBT genes contributed to the taxol biosynthetic pathway along with the accumulation of some taxanes in needles and stems of Taxus baccata over year 2013-2014. In both tissues, light intensity and temperature correlated with the production of 10-DAB III and total taxanes, and TXS activity, while a lack of significant association was deduced for day length and relative humidity. Furthermore, in both tissues, a weak correlation was observed between BAC III and light intensity, temperature, day length and relative humidity, and the corresponding gene, DBAT. Surprisingly, DBAT activity was not co-induced with TXS in both tissues, and remained expressed at basal levels over year, supporting that the conversion of 10-DAB III into BAC III could presumably be a rate limiting step in the taxol biosynthetic pathway. Similar to BAC III, no strong correlation was detected between production of taxol in both tissues and all the meteorological data, while the corresponding genes BAPT and DBTNBT, in some cases, exhibited significant correlated results. Notably, despite higher activities of BAPT and DBTNBT in both tissues over year, taxol production was still in small quantities, probably owing to the low amounts of its precursors rather than low volumes of BAPT and DBTNBT transcripts. The results, altogether, could provide us new insights towards the potential regulatory roles of environmental cues on the production of taxanes in yew trees.
authors.affiliation: Division of Plant Molecular Genetics, Department of Agronomy and Plant Breeding, Agricultural and Natural Resources College, University of Tehran, Karaj, Iran. jaber.nasiri@ut.ac.ir.
authors.forename: Jaber
authors.initials: J
authors.lastname: Nasiri
authors.affiliation: Division of Plant Molecular Genetics, Department of Agronomy and Plant Breeding, Agricultural and Natural Resources College, University of Tehran, Karaj, Iran. mnaghavi@ut.ac.ir.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Naghavi
authors.affiliation: Division of Plant Molecular Genetics, Department of Agronomy and Plant Breeding, Agricultural and Natural Resources College, University of Tehran, Karaj, Iran.
authors.forename: Houshang
authors.initials: H
authors.lastname: Alizadeh
authors.affiliation: Department of Horticultural Sciences, Agricultural and Natural Resources College, University of Tehran, Karaj, Iran.
authors.forename: Mohammad Reza Fattahi
authors.initials: MR
authors.lastname: Moghadam
mesh_terms: D053898:Biosynthetic Pathways; D004777:Environment; D018506:Gene Expression Regulation, Plant; D006813:Humidity; D017239:Paclitaxel / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018547:Plant Stems / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D012621:Seasons; D013472:Sunlight; D043823:Taxoids / Q000378:metabolism*; D020946:Taxus / Q000235:genetics* / Q000502:physiology / Q000528:radiation effects; D013696:Temperature; D015533:Transcriptional Activation
chemical_list: D010940:Plant Proteins; D043823:Taxoids; D017239:Paclitaxel
keywords: Gene expression; Meteorological parameters; Seasonal changes; Taxanes; Taxus baccata