Nicotiana benthamiana, a tobacco species from the Solanaceae family, originates from Australia and is not typically cultivated for smoking purposes. Its significance lies in scientific research, where it serves as a crucial tool due to its genetic malleability and rapid growth cycle.

Botanical Classification

Kingdom: Plantae
Clade: Tracheophytes, Angiosperms, Eudicots, Asterids
Order: Solanales
Family: Solanaceae
Genus: Nicotiana
Species: N. benthamiana

Plant Characteristics

Nicotiana benthamiana reaches up to 1-2 meters in height with a bushy appearance, sporting large, velvety leaves that are sticky to the touch. The plant's flowers are white and tubular, blooming profusely and attracting pollinators, although it is primarily propagated through seeds in research settings.

Chemical Composition and Structure

This plant's chemical profile includes lower nicotine levels compared to commercial tobacco but contains other significant alkaloids and various defensive compounds such as proteinase inhibitors and polyphenols. These substances contribute to its utility in plant-pathogen interaction studies.

How to Cultivate It

To grow Nicotiana benthamiana:

1. Soil: Plant in well-draining, fertile soil.
2. Light: Requires full sunlight.
3. Watering: Moderate, consistent watering is necessary, being cautious not to overwater.
4. Temperature: Warm conditions are critical, as the plant is frost-sensitive.
5. Planting: Start from seeds indoors and transplant outdoors after the risk of frost has passed. The plant matures quickly, making it suitable for multiple planting cycles in a year under the right conditions.

Uses and Benefits

Primarily, Nicotiana benthamiana is instrumental in molecular biology, serving as a model for studying viral diseases in plants and as a production system for pharmaceutical proteins, including antibodies and vaccines.

Applications

• Medical: The plant's fast lifecycle and susceptibility to viral vectors make it an ideal host for developing viral vectors and expressing recombinant proteins, including vaccines against influenza and COVID-19.
• Cosmetics: Although less common, extracts could be investigated for use in skincare products due to antioxidant properties.
• Other: It is pivotal in genetic engineering research for gene silencing and gene expression studies due to its easy transformation characteristics.

Environmental and Safety Considerations

While Nicotiana benthamiana is regarded as safe within controlled environments (e.g., laboratories), its alkaloid content requires careful handling to avoid potential toxicity. Environmentally, precautions should be taken to ensure that it does not escape cultivation and establish in non-native ecosystems, where it might compete with local flora. 

Sustainable and ethical research practices are emphasized to mitigate any ecological impact.

References__________________________________________________________________________

Bally J, Jung H, Mortimer C, Naim F, Philips JG, Hellens R, Bombarely A, Goodin MM, Waterhouse PM. The Rise and Rise of Nicotiana benthamiana: A Plant for All Reasons. Annu Rev Phytopathol. 2018 Aug 25;56:405-426. doi: 10.1146/annurev-phyto-080417-050141.

Abstract. A decade ago, the value of Nicotiana benthamiana as a tool for plant molecular biologists was beginning to be appreciated. Scientists were using it to study plant-microbe and protein-protein interactions, and it was the species of choice with which to activate plasmid-encoded viruses, screen for gene functions with virus-induced gene silencing (VIGS), and transiently express genes by leaf agroinfiltration. However, little information about the species' origin, diversity, genetics, and genomics was available, and biologists were asking the question of whether N. benthamiana is a second fiddle or virtuoso. In this review, we look at the increased knowledge about the species and its applications over the past decade. Although N. benthamiana may still be the sidekick to Arabidopsis, it shines ever more brightly with realized and yet-to-be-exploited potential.

Goodin MM, Zaitlin D, Naidu RA, Lommel SA. Nicotiana benthamiana: its history and future as a model for plant-pathogen interactions. Mol Plant Microbe Interact. 2008 Aug;21(8):1015-26. doi: 10.1094/MPMI-21-8-1015. 

Abstract. Nicotiana benthamiana is the most widely used experimental host in plant virology, due mainly to the large number of diverse plant viruses that can successfully infect it. Additionally, N. benthamiana is susceptible to a wide variety of other plant-pathogenic agents (such as bacteria, oomycetes, fungi, and so on), making this species a cornerstone of host-pathogen research, particularly in the context of innate immunity and defense signaling. Moreover, because it can be genetically transformed and regenerated with good efficiency and is amenable to facile methods for virus-induced gene silencing or transient protein expression, N. benthamiana is rapidly gaining popularity in plant biology, particularly in studies requiring protein localization, interaction, or plant-based systems for protein expression and purification. Paradoxically, despite being an indispensable research model, little is known about the origins, genetic variation, or ecology of the N. benthamiana accessions currently used by the research community. In addition to addressing these latter topics, the purpose of this review is to provide information regarding sources for tools and reagents that can be used to support research in N. benthamiana. Finally, we propose that N. benthamiana is well situated to become a premier plant cell biology model, particularly for the virology community, who as a group were the first to recognize the potential of this unique Australian native.

Reed J, Osbourn A. Engineering terpenoid production through transient expression in Nicotiana benthamiana. Plant Cell Rep. 2018 Oct;37(10):1431-1441. doi: 10.1007/s00299-018-2296-3. 

Abstract. Terpenoids are the most structurally diverse class of plant natural products with a huge range of commercial and medical applications. Exploiting this enormous potential has historically been hindered due to low levels of these compounds in their natural sources, making isolation difficult, while their structural complexity frequently makes synthetic chemistry approaches uneconomical. Engineering terpenoid biosynthesis in heterologous host production platforms provides a means to overcome these obstacles. In particular, plant-based production systems are attractive as they provide the compartmentalisation and cofactors necessary for the transfer of functional pathways from other plants. Nicotiana benthamiana, a wild relative of tobacco, has become increasingly popular as a heterologous expression platform for reconstituting plant natural product pathways, because it is amenable to Agrobacterium-mediated transient expression, a scalable and highly flexible process that enables rapid expression of genes and enzymes from other plant species. Here, we review recent work describing terpene production in N. benthamiana. We examine various strategies taken to engineer this host for increased production of the target metabolite. We also look at how transient expression can be utilised for rapid generation of molecular diversity, including new-to-nature products. Finally, we highlight current issues surrounding this expression platform and discuss the future directions and developments which will be needed to fully realise the potential of this system.