Plant Molecular Farming (PMF) capitalizes on the unique properties of plants as bioreactors to efficiently produce valuable proteins, pharmaceuticals, and enzymes. This review emphasizes the critical role of transient expression systems, particularly in Nicotiana benthamiana, due to its susceptibility to various pathogens. Viral vector-based transient expression has proven essential during health emergencies like COVID-19, enabling rapid recombinant protein production. The review also evaluates different transient expression platforms and highlights their applications in biopharmaceutical production, education, synthetic biology, and gene editing. Advances in viral vector modification, hydroponics, and Controlled Environment Agriculture (CEA) are presented as transformative innovations enhancing scalability and regulatory compliance. Furthermore, glycoengineering advancements broaden the range of producible biopharmaceuticals, improving global medication access. By exploring these advancements, this review underscores the vast potential of transient expression systems to meet dynamic scientific and market demands, positioning PMF as a vital component in modern biotechnology.

Environmental toxins pose significant threats to ecosystems and human health. Monitoring and assessing these toxins are crucial for effective environmental management and public health protection. Recently, plant species have garnered increasing attention as potential bioindicators for identifying and evaluating ecological toxins. Since plants often come into touch with harmful compounds in soil, water, and the atmosphere, they are particularly valuable for analyzing how human activities influence the terrestrial ecosystem, the aquatic system, and the atmosphere. This review paper emphasizes using plant species as a resource for tracking environmental pollution and analyzing contaminants. We focused on plants because they are significant indicators of soil, water, and air quality changes. Many plants have been used as bio-indicators to assess and predict pollution, toxicity, and environmental changes. These include Allium cepa, Vicia faba, Pisum sativum, Zea mays, Nicotiana tabacum, lichens, and mosses. The idea of bioindicators is discussed in the current paper, with a focus on plants as possible candidates for bioindicators for toxin assessment and related outcomes.

The domain of the unknown function (DUF) gene families assumes pivotal roles in plant metabolic and stress responses. However, our comprehension of the tobacco DUF668 (NtDUF668) gene family and its specific reactions to heavy metal, drought, and salt stresses remain circumscribed. In the current investigation, a comprehensive genome-wide analysis of the NtDUF668 gene family was undertaken utilizing bioinformatics tools. The results unveiled a total of 20 members in the NtDUF668 gene family, denominated NtDUF668-01 to NtDUF668-20. Phylogenetic analyses indicated a closer genetic relationship of DUF668 genes between Nicotiana tabacum and Ipomoea batatas. The examination of gene structure and conservative motifs revealed a bifurcation into two major Clades, aligning with previous studies on DUF668 gene families from various plant species, emphasizing its highly conserved evolutionary mechanism across plants. The exploration of promoter regions of NtDUF668 genes revealed a plethora of cis-acting elements associated with abiotic and biotic stresses, light signaling, and phytohormones. Gene duplication events and selection pressure analysis disclosed the segmental duplication and strong purifying selection pressure during the evolution of NtDUF668 genes. Syntenic analysis indicated a relatively conserved evolutionary mechanism of DUF668 gene families within dicotyledons. Tissue-specific expression analysis suggested that NtDUF668 family members are potentially involved in root development, floral organ formation, and abscission. The expression patterns and qRT–PCR analysis of NtDUF668 genes implied the potentially functional involvements of NtDUF668s in response to multiple abiotic stresses. Furthermore, the stress-triggered member NtDUF668-08 exhibited specific nuclear localization. In conclusion, this genome-wide analysis illuminates the composition, phylogenetic relationships, and potential roles of the NtDUF668 gene family in abiotic stress responses. The identified candidate genes, particularly NtDUF668-08, warrant further research for functional investigation.

Pathogenesis-related 1 (PR1) proteins are important components of plant defense and stress responses and also serve as precursors of CAP-derived peptides (CAPE), a class of small bioactive peptides involved in immune and stress signaling. Despite their potential biological significance, CAPE-producing PR1 genes have not been systematically characterized in tobacco (Nicotiana tabacum). In this study, a genome-wide analysis identified 17 CAPE-producing PR1 genes, designated NtCAPE1 to NtCAPE17, in the tobacco genome. These genes encode proteins containing conserved CAP domains and N-terminal signal peptides, with predicted hydrophilic properties and mainly vacuolar localization, indicating conserved structural features within the family. Phylogenetic analysis, gene structure organization, conserved motif profiling, chromosomal distribution, and synteny analyses revealed both evolutionary conservation and duplication-driven diversification of the NtCAPE family. Promoter cis-element analysis showed enrichment of regulatory elements associated with phytohormone signaling, development, and stress responses. Public transcriptomic datasets revealed dynamic and gene-specific expression patterns under water-deficit and salinity stress, and qRT-PCR analysis further confirmed the stress-responsive expression of selected NtCAPE genes. Functional assays using synthetic mature peptides showed that NtCAPE9 and NtCAPE17 alleviated salinity stress- and osmotic stress-induced leaf yellowing, improved chlorophyll retention, suppressed senescence-associated responses, reduced H₂O₂ accumulation and POD activity, modulated stress-responsive gene expression, and promoted seed germination under salinity and osmotic stress, respectively. These results provide a comprehensive characterization of CAPE-producing PR1 genes in tobacco and identify NtCAPE9 and NtCAPE17 as candidate stress-associated peptides with exogenous activity under salinity and osmotic stress conditions.