RNAi based simultaneous silencing of all forms of light-dependent NADPH:protochlorophyllide oxidoreductase genes result in the accumulation of protochlorophyllide in tobacco (Nicotiana tabacum)

Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Bibliographische Detailangaben
Veröffentlicht in:Plant physiology and biochemistry : PPB. - 1991. - 71(2013) vom: 01. Okt., Seite 31-6
1. Verfasser: Talaat, Neveen B (VerfasserIn)
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2013
Zugriff auf das übergeordnete Werk:Plant physiology and biochemistry : PPB
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Chlorophyll biosynthesis Gene silencing Light-dependent NADPH:Pchlide oxidoreductases (POR) Protochlorophyllide siRNA 20369-67-9 NADP 53-59-8 mehr... Oxidoreductases EC 1.-
Beschreibung
Zusammenfassung:Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Conversion of protochlorophyllide (Pchlide) into chlorophyllide (Chlide), a key step in chlorophyll biosynthesis, is mediated by a light-dependent NADPH:protochlorophyllide oxidoreductase (POR). POR exists in multiple isoforms that share high degree of homology. RNAi-mediated gene silencing approach was used to suppress the expression of POR genes in order to study its role in the Chls biosynthesis in tobacco (Nicotiana tabacum L.). The transgenic plants were devoid of chlorophyll pigments and resembled albino plants. Northern blot analysis confirmed the degradation of POR transcripts into 21-23 bp fragments. Pigment analysis showed the accumulation of various intermediate compounds of Chl biosynthesis pathway including Pchlide. However, no trace of chlorophyll was observed. As compared to wild type, POR-silenced plants accumulated larger (60%) amounts of Pchlide from its endogenous substrate. When leaf discs of WT and POR-silenced plants were treated with exogenous ALA both WT and POR-silenced plants accumulated large amounts of tetrapyrrolic intermediates demonstrating that Pchlide biosynthesis potential was not suppressed in POR-silenced plants. Upon illumination, WT plants photo-transformed large amounts of Pchlide to Chlide. However, POR-silenced plants almost completely failed to do so. Results demonstrate that the antisense approaches to drop expression of individual POR isoforms have provided valuable insights into the role of distinct PORs during greening. Moreover, data illustrate that the POR is the only enzyme that can convert the Pchlide to Chlide and there is no alternate enzyme that can substitute the POR in higher plants. Thus, this investigation describes ideal mechanism for the silencing of POR isozymes in tobacco
Beschreibung:Date Completed 02.05.2014
Date Revised 13.12.2023
published: Print-Electronic
Citation Status MEDLINE
ISSN:1873-2690
DOI:10.1016/j.plaphy.2013.06.025