8 research outputs found
Early detection of the orchid flowering gene PaFT1 in tobacco cells using a GFP reporter
No full textHere we describe a novel method of using green fluorescence protein (GFP) as a reporter gene for early detection of an integrated TDNA containing the orchid flowering gene, PaFT1 (Phalaenopsis aphrodite Flowering locus T1) in the tobacco genome. Functional assays that report the presence of exogenous DNA early in development are especially useful in plants where the desired phenotype is only apparent after long periods of vegetative growth. The objective of this study is to establish a method for detecting an inserted Phalaenopsis orchid flowering gene and examining its function in tobacco. The p35S::PaFT1 35S::GFP construct was introduced into Agrobacterium tumefaciens strain EHA101. Transformed tobacco leaves were cultured on MS medium with addition of 1 mgL-1 NAA+3 mgL-1 BAP+50 mgL-1 Kanamycin+300 mgL-1 timentin for selection. Results showed bright green GFP fluorescent signals in 11 out of 15 (73%) tobacco leaf cells at a 2month time point after transformation. GFP and PaFT1 fragments were amplified in genomic PCR using GFP and PaFT1 specific primers. The accumulated PaFT1 transcripts were observed in 3 monthold transgenic tobacco plants containing p35S::PaFT135S::GFP. Green florescence was observed only in the transgenic plants at the 5 monthold stage but not in the wild type controls
Stable Transformant of Phalaenopsis amabilis Somatic Embryo Carrying 35S::AtRKD4 Develops Into Normal Phenotype of Transgenic Plant
No full textPhalaenopsis amabilis (L.) Blume orchid is an Indonesian national flower. The number of these orchids in their natural habitat is very limited, therefore plant propagation efforts are needed. One of the promising methods is plant propagation by inserting embryo gene AtRKD4 from a model plant Arabidopsis thaliana into the orchid genome to produce many somatic embryos. From previous research, we have obtained 28 plant P. amabilis transformants carrying the AtRKD4 gene, however, it was unknown whether these plants have normal phenotypes and growth similar to their parents. Therefore, descriptions on growth and morphology are needed. This research aimed to evaluate the phenotype of P. amabilis carrying 35S::AtRKD4 the transformants grown in greenhouse. To achieve it, AtRKD4 gene integration stability on transformants genome was analyzed. Morphology and cross-section anatomy structure on transformant and non-transformant plantswere described. The stability of AtRKD4 gene integration in the plant genome was confirmed by amplification of the AtRKD4 gene from genomic DNA with Polymerase Chain Reaction (PCR) using a specific primer for AtRKD4 and ACTIN genes as the internal control. The quantitative data from morphology and anatomy measurements were analyzed statistically using ANOVA. The results showed that AtRKD4 was stably integrated into the genome of P. amabilis transformants and all transformant plants showed similar morphology and anatomy characteristics as non-transformant plants. The AtRKD4 embryo gene was stably integrated into the orchid genome and the transformant plants grow normally without significant changes in phenotype
In Vitro Germination and Flowering of Dendrobium capra J.J. Smith, An Endemic Orchid of Java
No full textDendrobium capra is an Indonesian endemic orchid species that live in Java. It grows on low altitude with warm climate. D. capra has beautiful small yellow greenish flower that grow in raceme inflorescence. This orchid faces a threat in its natural habitat due to having a long life cycle and a forestry main commodity as a main host thus categorized as Appendix II on CITES list. To address that problem, ex situ conservation approach using in vitro culture method is necessary. Germination enhancement effort using complex organic substances found that 200 ml/l tomato extract gave best germination result. Analysis on D. capra plantlet growth also showed that MS medium produced better plantlet size than NP, VW and KC medium. Supplementing medium with a combination of NAA and TDZ has also successfully induced early flowering within 11 month of culture period. This information is important to achieve successful in vitro culture of D. capra for various purposes
Sequence Variation and In Silico Protein Characterization of γ-TMT Gene in Mutant Rodent Tuber (Typhonium flagelliforme Lodd.)
No full textγ-tocopherol is an important antioxidant compound associated with anticancer activity in several plants. This study aimed to analyze the γ-TMT (γ-tocopherol methyltransferase) gene sequence and predict its protein structure in mutant rodent tuber (Typhonium flagelliforme Lodd.) plants. Degenerate primers were designed from homologous sequences in monocot species and used to amplify the γ-TMT gene. Amplification of the γ-TMT gene was observedin the mutant and the wild-type plants. The amplified region partially covers the γ-TMT gene, which has undergone mutations due to a combination of somaclonal variation and gamma irradiation. Sequence analysis revealed notable variations between mutant and wild-type lines, including base substitutions and deletions. Predicted protein structures based on the coding DNA sequence (CDS) revealed notable differences in helix and loop orientation, particularly in the C-terminal domain and central regions of the protein. These structural differences suggest potential links to increased tocopherol biosynthesis or biological activity; however, further experimental validation is required to confirm these functional implications. This study provides foundational insights into the link between the expression of the γ-TMT gene and tocopherol biosynthesis and supports the development of specific molecular markers in T. flagelliforme
Agrobacterium-mediated transformation facillitates the CRISPR/Cas9 genome editing system in Dendrobium macrophyllum A. Rich orchid
No full textDevelopment of an agrobacterium-delivered CRISPR/Cas9 for Phalaenopsis amabilis (L.) Blume genome editing system
No full textApplication of CRISPR/Cas9 genome editing system for molecular breeding of orchids
No full textOrchid is an important ornamental plant in Indonesia due to their natural beauty of flowers. In the tropical forest, orchids are being acquired for trading and commercial market. Thus, the effort is required to proliferate orchid in large quantities for conservation and improve the floral variation for plant breeding. The purpose of this study is to develop a firmed methodology of molecular breeding of orchids using CRISPR/Cas9 KO system. The plant material used was Phalaenopsis amabilis protocorms growth on NP medium+pepton (2 g/L). Protocorm were submerged in the culture of Agrobacterium tumefaciens that Ti‐plasmid had been filled with a T‐DNA construct of a pRGEB32 vector harboring sgRNA with PDS3 sequence. Detection for transformants was confirmed by PCR using HPT primers (545 bp), Cas9 primers (402 bp), PDS primers (280 bp) and trnL‐F (1200 bp) as an internal control. The results showed that 0.96% PDS transformants were obtained from PDS3T2 lines. Several transformant showed pale leaf color compared to non‐transformant plants. This study suggests that the target gene has successfully edited by CRISPR/Cas9 system and could be applied for that functional gene editing in orchids
Impact of a blood-stage vaccine on Plasmodium vivax malaria
No full textBACKGROUND: There are no licensed vaccines against Plasmodium vivax, the most common cause of malaria outside of Africa. METHODS: We conducted two Phase I/IIa clinical trials to assess the safety, immunogenicity and efficacy of two vaccines targeting region II of P. vivax Duffy-binding protein (PvDBPII). Recombinant viral vaccines (using ChAd63 and MVA vectors) were administered at 0, 2 months or in a delayed dosing regimen (0, 17, 19 months), whilst a protein/adjuvant formulation (PvDBPII/Matrix-M(™)) was administered monthly (0, 1, 2 months) or in a delayed dosing regimen (0, 1, 14 months). Delayed regimens were due to trial halts during the COVID-19 pandemic. Volunteers underwent heterologous controlled human malaria infection (CHMI) with blood-stage P. vivax parasites at 2–4 weeks following their last vaccination, alongside unvaccinated controls. Efficacy was assessed by comparison of parasite multiplication rate (PMR) in blood post-CHMI, modelled from parasitemia measured by quantitative polymerase-chain-reaction (qPCR). RESULTS: Thirty-two volunteers were enrolled and vaccinated (n=16 for each vaccine). No safety concerns were identified. PvDBPII/Matrix-M(™), given in the delayed dosing regimen, elicited the highest antibody responses and reduced the mean PMR following CHMI by 51% (range 36–66%; n=6) compared to unvaccinated controls (n=13). No other vaccine or regimen impacted parasite growth. In vivo growth inhibition of blood-stage P. vivax correlated with functional antibody readouts of vaccine immunogenicity. CONCLUSIONS: Vaccination of malaria-naïve adults with a delayed booster regimen of PvDBPII/Matrix-M(™) significantly reduces the growth of blood-stage P. vivax
