Transgene expression systems in the Triticeae cereals

Isolation and characterization of rubisco small subunit gene promoter from common wheat (Triticum aestivumL.)

“…Alternatively, adding other regions of the gene such as the first intron to the promoter might enhance its efficiency of directing gene expression, as observed for some other promoters such as Ubi1 and Act1. 5 Since the TarbcS promoter identified in this study represents only a partial fragment, we cannot exclude the possibility that other regulatory elements required for a strong expression are missing. The TarbcS:GUS construct was also used to examine the functionality of the newly isolated promoter fragment in wheat root, a tissue that normally grows with no exposure to light.…”

“…The Ubi1 and Act1 promoters are often used with their first untranslated exon and intron, as inclusion of these elements results in strong expression of the transgene. 5 The other kinds of promoters used in transgene expression are the tissue/stage specific promoters that restrict the expression of transgenes in targeted tissues or developmental stages, and thereby reduce unintended effects in non-target tissues/stages. Some examples of such promoters include the seedspecific high molecular weight glutenin subunit (HMW-GS) promoter isolated from monocot species, 6 and the promoter derived from the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) of dicot species, 7 which is activated specifically in the photosynthetic tissues.…”

A roadmap for gene functional characterisation in wheat

“…The generation of stable transgenic lines in wheat most commonly involves the transformation of immature wheat embryos and subsequent callus regeneration (Harwood, 2012). Using transgenic approaches, gene expression can be altered in a variety of ways such as overexpressing or ectopically expressing the gene of interest using either constitutive, tissue-specific or inducible promoters (Hensel et al, 2011). Similarly, RNA-interference (RNAi) has been used successfully in wheat to reduce gene expression with the added benefit that constructs can be designed to target all homoeologous genes simultaneously, thereby overcoming the potential drawback of functional redundancy among homoeologs (Fu et al, 2007).…”

Transient Virus Expression Systems for Recombinant Protein Expression in Dicot- and Monocotyledonous Plants

“…As with dicot expression vectors, monocot vectors include both minimal and independent virus vectors [103]. As noted above, minimal type BMV vectors have been constructed by replacing the coat protein ORF with a foreign gene.…”