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Ethylene, the simplest gaseous plant growth regulator (PGR), controls diverse physiological pathways in plants. Under various stress conditions and during different developmental stages, such as root elongation, leaf and flower senescence, seed germination, tissue differentiation and organ abscission, ethylene biosynthesis is significantly increased. In rice, the internal ethylene concentration is rapidly regulated to a genetically, physiologically and morphologically relevant level under various stresses. Regulation of the ethylene signalling pathway under adverse conditions results in up- and/or down-regulation of the expression of stress-related genes in different families. Transcription factors are proteins that influence and control a number of biological processes under both normal and stress conditions. APETALA 2/ethylene response factor (AP2/ERF) is a transcription factor that is considered to function in stress response pathways in rice. To date, many AP2/ERF genes have been functionally characterised in rice. An understanding of the interactions between the AP2/ERF genes and ethylene-dependent mechanisms may provide new insights to facilitate the enhanced adaptation of rice to stress. In the current review, the structure and function of ethylene in rice under normal and stress conditions are described, and then the general functions of the plant AP2/ERF transcription factors are discussed. In addition, the interactions between the AP2/ERF genes and ethylene pathways under abiotic stresses, including submergence, cold, salinity, drought and heavy metal stresses, as well as those under biotic stresses, are summarised. Although the AP2/ERF genes have been identified, information on the physiological mechanisms of this gene family under stress conditions in rice remains limited. Therefore, further physiological studies must be performed in the future to identify additional features of this crucial gene family. [ABSTRACT FROM AUTHOR]

The protoplast system is robust and versatile for plant genetic engineering works. There are various ways to deliver nucleic acid materials into the protoplasts, but polyethylene glycol (PEG)-mediated method offers minimal damage compared to others. Therefore, an established PEG-mediated transformation protocol with optimised parameters is needed to improve the system's reproducibility and reliability. This study utilised oil palm mesophyll protoplasts as transformation cells and the red fluorescent protein (DsRED) as a visual reporter. Based on the transformation efficiency scored after 72 h, a method with the following parameters: 5 min incubation in 35% PEG, 10 min incubation with 50 µg DNA, and 90 s heat-shock treatment at 42 °C was found to be the best for oil palm protoplast PEG-mediated transfection. A significant improvement in transformation efficiency at about 56% was achieved using this method compared to the previous study (5%). This newly developed protocol was then used to evaluate the efficiency in terms of the relative strength of 7 promoters, including two plant constitutive promoters, three oil palm constitutive promoters, and two oil palm tissue-specific promoters in regulating the expression of the transgene in oil palm. Based on the results from three individual replicates, CaMV35S showed to be the most efficient amongst the tested promoters in driving the transgene expression in oil palm mesophyll protoplasts, followed by oil palm translationally control tumour protein (TCTP) and maize-ubiquitin (Ubi1) promoters. [Display omitted] • An efficient PEG-mediated transformation of oil palm mesophyll protoplasts. • High transformation efficiency compared to the previous protocol. • A reliable and reproducible oil palm protoplast-based transient gene expression assay. • The CaMV35S promoter was efficient for transgene expression in oil palm protoplasts. [ABSTRACT FROM AUTHOR]

• An efficient protocol for protoplasts isolation from in vitro leaf and mesocarp of oil palm has been established. • Enzymes composition effect on the yield and viability of protoplast are significant. • Scraping the waxy layer on oil palm leaf increased the protoplast isolation efficiency. • Vacuum treatment enhanced the penetration of enzymes into tissues. • 10% ficoll in 0.6 M mannitol improved the separation of protoplasts from impurities. The absence of a cell wall on the protoplast contributes to its versatility. Its flexibility for DNA manipulation and the possibility of rapid cell-based assay is desirable in the plant biotechnology field. This study was carried out to improve protoplast isolation from oil palm in vitro leaf and mesocarp tissues. The factors affecting protoplast isolation efficiency were optimized, including the protocols and enzyme composition involved, focusing on the oil palm in vitro leaf first. Incubation of oil palm leaf sample with an enzyme mixture of cellulase R-10, macerozyme R-10, driselase, and pectolyase Y-23, for 14 h has successfully produced up to 2.5 × 106 protoplasts g-1 fresh weight (FW)-1 with 95% viability. Incubation of oil palm mesocarp tissue with the optimized enzyme mixture for 2 h at static condition has also successfully produced 3.98 × 106 protoplasts g-1 FW-1 with 85% viability. Besides, it was found that increasing the sample's surface area in contact with enzyme solution by slicing the samples into narrow strips and thin layers has improved the penetration of enzymes into the tissues and enhanced the isolation efficiency. In addition, a plasmolysis step before enzymatic treatment has also improved the protoplast viability by minimizing the damage incurred during isolation. The successful isolation of protoplast from oil palm leaf and mesocarp has enabled the study of gene function and the characterization of endogenous tissue-specific promoter being carried out in vivo. [ABSTRACT FROM AUTHOR]

• First report on the use of Discosoma red fluorescent protein (DsRED) - as visual reporter marker in oil palm cells. • Seven DsRED gene vectors driven by a different promoter were constructed and available for the scientific community. • The expression of DsRED in oil palm cells exhibited better photostability and brightness compared to GFP. Genetic modification of oil palm is being carried out to explore new avenues for improving and expanding the potential of oil palm. Multiple bottlenecks in delivering the DNA into oil palm cells and generating the transgenic oil palm required us to look into an alternative marker which could help us assess the efficiency of the transformation system, moreover at the early stage considering that oil palm is a slow growing plant. In this study, we have constructed seven transformation vectors carrying a gene encoding DsRED, each driven by a different promoter, i.e. plant constitutive promoter, oil palm constitutive promoter or oil palm tissue-specific promoter. The vectors were transformed into oil palm embryogenic calli via microprojectile bombardment and the red fluorescence signals were observed after 48 h. Based on the observation, the construct driven by the CaMV35S promoter produced the highest number of red fluorescent spots. The oil palm calli bombarded with pUbi-DsRED plasmid suffered the most number of red fluorescent spots losses from day three until day 42, as compared to other constructs. The red fluorescent signals of DsRED produced across all transformed samples appeared to be bright and very distinctive as compared to the background. [ABSTRACT FROM AUTHOR]

Any forms of valorization of microorganisms would require accurate identity recognition to ensure repeatability, reproducibility and quality assurance. This study aimed to evaluate the effectiveness of different primers for identifying cultured eukaryotic microalgae using a simple 18S rDNA approach. A total of 34 isolated microalgae and one culture collection were utilized in the search for an effective molecular identification method for microalgae. Ammonium formate was applied to marine microalgae prior to DNA extraction. The microalgal DNA was extracted using a commercial kit and subjected directly to PCR amplification using four different published 18S rDNA primers. The DNA sequences were analysed using Basic Local Alignment Search Tool (BLAST) and phylogenetic trees to determine the microalgae identity. The identity was further validated with conventional morphological taxonomic identification, and the relationship of microalgal morphology and genetic materials was also determined. The microalgal DNA was successfully amplified, including marine species without prior cleaning. In addition, the ss5 + ss3 primer pair was found to be an ideal primer set among the tested primers for identifying microalgae. Overall, molecular identification showed relative matching with morphological identification (82.86%). This study is important because it serves as a platform to develop a standardized eukaryotic microalgae identification method. In addition, this method could help to ease the eukaryotic microalgae identification process and enrich the current reference databases such as GenBank. • Effectiveness of different published primers was tested on 35 cultured microalgae. • Marine microalgae do not require desalting process prior to PCR amplification. • Same molecular identification approach could apply to freshwater and marine microalgae. • ss5 + ss3 primer pair showed the highest universality in identifying microalgae. • 82.86% matching between molecular and morphological identification at the genus level. [ABSTRACT FROM AUTHOR]

Modification of lipid composition in the mesocarp tissue of oil palm involves genetic manipulation of multiple genes. More than one mesocarp-preferential promoter is necessary for the expression of individual transgenes in the same plant to obviate transcriptional gene silencing. This study aimed to identify genes that are preferentially expressed in the mesocarp tissue and characterize selected candidate mesocarp-preferential promoters. Ten transcripts that were preferentially expressed in the mesocarp tissue were identified from the analysis of 82 transcriptome datasets of 12 different oil palm tissues. The expression of two candidate genes, MSP-C1 and MSP-C6 , was verified to be preferentially expressed in the mesocarp tissues and shown to have a low expression level in non-mesocarp tissues by reverse transcription quantitative real-time PCR (RT-qPCR). MSP-C6 promoter fragments of different lengths were transformed into tomato plants for further characterization. Both unripe and ripe fruits of transgenic tomato plants transformed with a construct harboring the MSP-C6-F1 (2014 bp) promoter were shown to have high beta-glucuronidase (GUS) activities. The findings of this study suggest the potential applications of the MSP-C6 promoter as a molecular tool for genetic engineering of novel traits in fruit crops. • Ten mesocarp-preferential transcripts were identified from the analysis of 82 oil palm transcriptome datasets. • Two candidate genes were verified to be preferentially expressed in the oil palm mesocarp tissues. • The MSP-C6-F1 (2014 bp) promoter fragment was shown to be able to drive preferential gene expression in tomato fruits. • Characterization of mesocarp-specific promoters contribute to future genetic manipulation of oil synthesis in oil palm. [ABSTRACT FROM AUTHOR]

Artemisia vulgaris is one of the important medicinal plant species of the genus Artemisia , which is usually known for its volatile oils. The genus Artemisia has become the subject of great interest due to its chemical and biological diversity as well as the discovery and isolation of promising anti-malarial drug artemisinin. A. vulgaris has a long history in treatment of human ailments by medicinal plants in various parts of the world. This medicinal plant possesses a broad spectrum of therapeutic properties including: anti-malarial, anti-inflammatory, anti-hypertensive, anti-oxidant, anti-tumoral, immunomodulatory, hepatoprotective, anti-spasmodic and anti-septic. These activities are mainly attributed to the presence of various classes of secondary metabolites, including flavonoids, sesquiterpene lactones, coumarins, acetylenes, phenolic acids, organic acids, mono- and sesquiterpenes. Studies related to A. vulgaris morphology, anatomy and phytochemistry has gained a significant interest for better understanding of production and accumulation of therapeutic compounds in this species. Recently, phytochemical and pharmacological investigations have corroborated the therapeutic potential of bioactive compounds of A. vulgaris . These findings provided further evidence for gaining deeper insight into the identification and isolation of novel compounds, which act as alternative sources of anti-malarial drugs in a cost-effective manner. Considering the rising demand and various medical applications of A. vulgaris , this review highlights the recent reports on the chemistry, biological activities and biotechnological interventions for controlled and continuous production of bioactive compounds from this plant species. [ABSTRACT FROM AUTHOR]