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Over the last several decades, plants have been developed as a platform for the production of useful recombinant proteins due to a number of advantages, including rapid production and scalability, the ability to produce unique glycoforms, and the intrinsic safety of food crops. The expression methods used to produce target proteins are divided into stable and transient systems depending on applications that use whole plants or minimally processed forms. In the early stages of research, stable expression systems were mostly used; however, in recent years, transient expression systems have been preferred. The production of the plant itself, which produces recombinant proteins, is currently divided into two major approaches, open-field cultivation and closed-indoor systems. The latter encompasses such regimes as greenhouses, vertical farming units, cell bioreactors, and hydroponic systems. Various aspects of each system will be discussed in this review, which focuses mainly on practical examples and commercially feasible approaches. [ABSTRACT FROM AUTHOR]

Disease prevention through vaccination is considered to be the greatest contribution to public health over the past century. Every year more than 100 million children are vaccinated with the standard World Health Organization (WHO)-recommended vaccines including hepatitis B (HepB). HepB is the most serious type of liver infection caused by the hepatitis B virus (HBV), however, it can be prevented by currently available recombinant vaccine, which has an excellent record of safety and effectiveness. To date, recombinant vaccines are produced in many systems of bacteria, yeast, insect, and mammalian and plant cells. Among these platforms, the use of plant cells has received considerable attention in terms of intrinsic safety, scalability, and appropriate modification of target proteins. Research groups worldwide have attempted to develop more efficacious plant-derived vaccines for over 30 diseases, most frequently HepB and influenza. More inspiring, approximately 12 plant-made antigens have already been tested in clinical trials, with successful outcomes. In this study, the latest information from the last 10 years on plant-derived antigens, especially hepatitis B surface antigen, approaches are reviewed and breakthroughs regarding the weak points are also discussed. [ABSTRACT FROM AUTHOR]

Alternative splicing (AS) is an important molecular mechanism by which single genes can generate multiple mRNA isoforms. We reported previously that, in Oryza sativa, the cyclophilin 19-4 (OsCYP19-4.1) transcript was significantly upregulated in response to cold stress, and that transgenic plants were cold tolerant. Here we show that, under cold stress, OsCYP19-4 produces eight transcript variants by intron retention and exon skipping, resulting in production of four distinct protein isoforms. The OsCYP19-4 AS isoforms exhibited different cellular localizations in the epidermal cells: in contrast to OsCYP19-4.1, the OsCYP19-4.2 and OsCYP19-4.3 proteins were primarily targeted to guard and subsidiary cells, whereas OsCYP19-4.5, which consists largely of an endoplasmic reticulum (ER) targeting signal, was co-localized with the RFP-BiP marker in the ER. In OsCYP19-4.2, the key residues of the PPIase domain are altered; consistent with this, recombinant OsCYP19-4.2 had significantly lower PPIase activity than OsCYP19-4.1 in vitro. Specific protein-protein interactions between OsCYP19-4.2/3 and AtRCN1 were verified in yeast two-hybrid (Y2H) and bimolecular fluoresence complementation (BiFC assays), although the OsCYP19-4 isoforms could not bind each other. Based on these results, we propose that two OsCYP19-4 AS isoforms, OsCYP19-4.2 and OsCYP19-4.3, play roles linking auxin transport and cold stress via interactions with RCN1. [ABSTRACT FROM AUTHOR]

Cabbage is a relatively robust vegetable at low temperatures. However, at high temperatures, cabbage has disadvantages, such as reduced disease tolerance and lower yields. Thus, selection of heat-tolerant cabbage is an important goal in cabbage breeding. Easier or faster selection of superior varieties of cabbage, which are tolerant to heat and disease and have improved taste and quality, can be achieved with molecular and biological methods. We compared heat-responsive gene expression between a heat-tolerant cabbage line (HTCL), ?HO?, and a heat-sensitive cabbage line (HSCL), ?JK?, by Genechip assay. Expression levels of specific heat stress-related genes were increased in response to high-temperature stress, according to Genechip assays. We performed quantitative RT-PCR (qRT-PCR) to compare expression levels of these heat stress-related genes in four HTCLs and four HSCLs. Transcript levels for heat shock protein BoHsp70 and transcription factor BoGRAS (SCL13) were more strongly expressed only in all HTCLs compared to all HSCLs, showing much lower level expressions at the young plant stage under heat stress (HS). Thus, we suggest that expression levels of these genes may be early selection markers for HTCLs in cabbage breeding. In addition, several genes that are involved in the secondary metabolite pathway were differentially regulated in HTCL and HSCL exposed to heat stress. [ABSTRACT FROM AUTHOR]

The putative thylakoid lumen immunophilin, FKBP16-3, has not yet been characterized, although this protein is known to be regulated by thioredoxin and possesses a well-conserved CxxxC motif in photosynthetic organisms. Here, we characterized rice OsFKBP16-3 and examined the role of this gene in the regulation of abiotic stress in plants. FKBP16-3s are well conserved in eukaryotic photosynthetic organisms, including the presence of a unique disulfide-forming CxxxC motif in their N-terminal regions. OsFKBP16-3 was mainly expressed in rice leaf tissues and was upregulated by various abiotic stresses, including salt, drought, high light, hydrogen peroxide, heat and methyl viologen. The chloroplast localization of OsFKBP16-3-GFP was confirmed through the transient expression of OsFKBP16-3 in Nicotiana benthamiana leaves. Transgenic Arabidopsis and transgenic rice plants that constitutively expressed OsFKBP16-3 exhibited increased tolerance to salinity, drought and oxidative stresses, but showed no change in growth or phenotype, compared with vector control plants, when grown under non-stressed conditions. This is the first report to demonstrate the potential role of FKBP16-3 in the environmental stress response, which may be regulated by a redox relay process in the thylakoid lumen, suggesting that artificial regulation of FKBP16-3 expression is a candidate for stress-tolerant crop breeding [ABSTRACT FROM AUTHOR]