When plant virology met Agrobacterium: the rise of the deconstructed clones

Abstract

SummaryIn the early days of molecular farming, Agrobacterium‐mediated stable genetic transformation and the use of plant virus‐based vectors were considered separate and competing technologies with complementary strengths and weaknesses. The demonstration that ‘agroinfection’ was the most efficient way of delivering virus‐based vectors to their target plants blurred the distinction between the two technologies and permitted the development of ‘deconstructed’ vectors based on a number of plant viruses. The tobamoviruses, potexviruses, tobraviruses, geminiviruses and comoviruses have all been shown to be particularly well suited to the development of such vectors in dicotyledonous plants, while the development of equivalent vectors for use in monocotyledonous plants has lagged behind. Deconstructed viral vectors have proved extremely effective at the rapid, high‐level production of a number of pharmaceutical proteins, some of which are currently undergoing clinical evaluation.

Nattokinase: An Oral Antithrombotic Agent for the Prevention of Cardiovascular Disease

“…There are a variety of ways to produce NK in plant systems. A rapid method is the utilization of a transient expression system, which can produce high levels of recombinant protein within a relatively short period of time (four to seven days) [65,66,67,68,69]. Various virus-based transient vectors have been studied for use in PMF systems.…”

Transgenic plants as genetic models for studying functions of plant genes

“…Для агробактериальной транс-формации используют бинарные векторы, способные реплицироваться и в Escherichia coli, и в агробактерии. A. tumefaciens переносит в геном растений сегмент ДНК (T-область), расположенный между концевыми повторами (LB, RB) (Bourras et al, 2015;Peyret, Lomonossoff, 2015). В структуре Т-области генетической конструкции можно выделить два ключевых элемента (см.…”

Metabolic engineering of plants using a disarmed potyvirus vector

“…At this point the main objective in vector design was to maximize heterologous protein yield by maintaining essential elements for protein expression and deleting or providing in trans some of the non-essential functions leading to 'deconstructed' vectors (Gleba et al, 2007. These efforts resulted in a wide spectrum of gene expression vectors with robust replication and amplification capacity and with abolished systemic movement which in most cases was replaced by A. tumefaciens-mediated replicon delivery (Peyret and Lomonossoff, 2015).…”

“…From the many viruses used as backbones to develop virus-based expression systems, here, the most successful plant virus-based vectors are summarized briefly with special attention on gene expression systems (Peyret and Lomonossoff, 2015;Salazar-González et al, 2015). Probably the most famous 'deconstructed' gene expression vector based on a plant virus is magnICON, a hybrid system with elements from Tobacco mosaic virus (TMV) and Turnip vein clearing virus (TVCV), both belonging to the genus Tobamovirus, family Virgaviridae, with rigid rod shaped virions and a single stranded positive-sense RNA (ssRNA+) genome ( Figure 2A).…”

“…The new technologies of genome manipulation enabled the construction of infectious clones of plant viruses that both served as experimental purposes and heterologous protein production systems in plants. Several plant viruses were successfully used to construct vectors for foreign protein expression, making in effect an 'ally from the enemy' Peyret and Lomonossoff, 2015). Potyviruses produce a large polyprotein, which is processed co-and post-tanslationally by three viral encoded proteases resulting in ten mature gene products in equimolar amounts Ivanov et al, 2014).…”