Purple-leaved Ficus lyrata plants produced by overexpressing a grapevine VvMybA1 gene

Identification of key genes responsible for green and white colored spathes in Anthurium andraeanum (Hort.)

Modern anthuriums, Anthurium andraeanum (Hort.) are among the most popular flowering plants and widely used for interior decoration. Their popularity is largely attributed to the exotic spathes with different colors. Previous studies have reported color development in red spathe cultivars, but limited information is available on key genes regulating white and green colored spathes. This study analyzed anthocyanin, chlorophyll, and carotenoid contents as well as transcript differences in spathes of eight cultivars that differed in spathe colors ranging from red to white and green. Results showed that increased expression of a transcription factor AaMYB2 was associated with elevated levels of anthocyanin in spathes, but decreased expression of AaMYB2 and increased expression of AaLAR (leucoanthocyanidin reductase) and AaANR (anthocyanidin reductase) were accompanied with the accumulation of colorless proanthocyanidin, thus the white spathe. As to the green colored spathe, chlorophyll content in the green spathe cultivar was substantially higher than the other cultivars. Correspondingly, transcripts of chlorophyll biosynthesis-related genes AaHemB (porphobilinogen synthase) and AaPor (protochlorophyllide oxidoreductase) were highly upregulated but almost undetectable in white and red spathes. The increased expression of AaHemB and AaPor was correlated with the expression of transcription factor AaMYB124. Subsequently, qRT-PCR analysis confirmed their expression levels in nine additional cultivars with red, white, and green spathes. A working model for the formation of white and green spathes was proposed. White colored spathes are likely due to the decreased expression of AaMYB2 which results in increased expression of AaLAR and AaANR, and the green spathes are attributed to AaMYB124 enhanced expression of AaHemB and AaPor. Further research is warranted to test this working model.

Transformation of Long-Lived Albino Epipremnum aureum 'Golden Pothos' and Restoring Chloroplast Development

Chloroplasts are organelles responsible for chlorophyll biosynthesis, photosynthesis, and biosynthesis of many metabolites, which are one of key targets for crop improvement. Elucidating and engineering genes involved in chloroplast development are important approaches for studying chloroplast functions as well as developing new crops. In this study, we report a long-lived albino mutant derived from a popular ornamental plant Epipremnum aureum 'Golden Pothos' which could be used as a model for analyzing the function of genes involved in chloroplast development and generating colorful plants. Albino mutant plants were isolated from regenerated populations of variegated 'Golden Pothos' whose albino phenotype was previously found to be due to impaired expression of EaZIP, encoding Mg-protoporphyrin IX monomethyl ester cyclase. Using petioles of the mutant plants as explants with a traceable sGFP gene, an efficient transformation system was developed. Expressing Arabidopsis CHL27 (a homolog of EaZIP) but not EaZIP in albino plants restored green color and chloroplast development. Interestingly, in addition to the occurrence of plants with solid green color, plants with variegated leaves and pale-yellow leaves were also obtained in the regenerated populations. Nevertheless, our study shows that these long-lived albino plants along with the established efficient transformation system could be used for creating colorful ornamental plants. This system could also potentially be used for investigating physiological processes associated with chlorophyll levels and chloroplast development as well as certain biological activities, which are difficult to achieve using green plants.

Study of the VvMybA1 gene allele state of some colored and uncolored grapevine varieties

As a result of the work, genetic markers were created that were used to identify alleles of the VvMybA1 genes, which control the anthocyanin color of berries in grape varieties. Using these markers, alleles were identified in grape varieties belonging to different ecologicalgeographical groups. In the process of work, alleles were sequenced and compared with the NCBI database in order to identify their state and their belonging to a specific type of structure. In addition, these sequences were compared with each other to reveal the structural features of varieties with and without color of berries. Single nucleotide polymorphisms, structural features, and deletions in the structure of alleles were revealed.

Overview and detectability of the genetic modifications in ornamental plants

The market of ornamental plants is extremely competitive, and for many species genetic engineering can be used to introduce original traits of high commercial interest. However, very few genetically modified (GM) ornamental varieties have reached the market so far. Indeed, the authorization process required for such plants has a strong impact on the profitability of the development of such products. Considering the numerous scientific studies using genetic modification on ornamental species of interest, a lot of transformed material has been produced, could be of commercial interest and could therefore be unintentionally released on the market. The unintentional use of GM petunia in breeding programs has indeed recently been observed. This review lists scientific publications using GM ornamental plants and tries to identify whether these plants could be detected by molecular biology tools commonly used by control laboratories.

Arabidopsis AtPAP1 transcription factor induces anthocyanin production in transgenic Taraxacum brevicorniculatum

This study developed a new purple coloured Taraxacum brevicorniculatum plant through genetic transformation using the Arabidopsis AtPAP1 gene, which overproduced anthocyanins in its vegetative tissues. Rubber-producing Taraxacum plants synthesise high-quality natural rubber (NR) in their roots and so are a promising alternative global source of this raw material. A major factor in its commercialization is the need for multipurpose exploitation of the whole plant. To add value to the aerial tissues, red/purple plants of the rubber-producing Taraxacum brevicorniculatum species were developed through heterologous expression of the production of anthocyanin pigment 1 (AtPAP1) transcription factor from Arabidopsis thaliana. The vegetative tissue of the transgenic plants showed an average of a 48-fold increase in total anthocyanin content over control levels, but with the exception of pigmentation, the transgenic plants were phenotypically comparable to controls and displayed similar growth vigor. Southern blot analysis confirmed that the AtPAP1 gene had been integrated into the genome of the high anthocyanin Taraxacum plants. The AtPAP1 expression levels were estimated by quantitative real-time PCR and were highly correlated with the levels of total anthocyanins in five independent transgenic lines. High levels of three cyanidin glycosides found in the purple plants were characterized by high performance liquid chromatography-mass spectrum analysis. The presence of NR was verified by NMR and infrared spectroscopy, and confirmed that NR biosynthesis had not been affected in the transgenic Taraxacum lines. In addition, other major phenylpropanoid products such as chlorogenic acid and quercetin glycosides were also enhanced in the transgenic Taraxacum. The red/purple transgenic Taraxacum lines described in this study would increase the future application of the species as a rubber-producing crop due to its additional health benefits.