Biology subjects

Hurgobin, B.

Publications and source records attributed to Hurgobin, B..

3 recordsLinked to original sources

bioRxiv2024

Characterization of the Cannabis sativa glandular trichome epigenome

BackgroundThe relationship between epigenomics and plant specialised metabolism remains largely unexplored despite the fundamental importance of epigenomics in gene regulation and, potentially, yield of products of plant specialised metabolic pathways. The glandular trichomes of Cannabis sativa are an emerging model system that produce large quantities of cannabinoid and terpenoid specialised metabolites with known medicinal and commercial value. To address the lack of epigenomic data in plant specialised metabolism, glandular trichomes, and C. sativa, we mapped H3K4 trimethylation, H3K56 acetylation, H3K27 trimethylation post-translational modifications and the histone variant H2A.Z, using chromatin immunoprecipitation, in glandular trichomes, leaf, and stem tissues. Corresponding transcriptomic (RNA-seq) datasets were integrated, and tissue-specific analyses conducted to relate chromatin states to glandular trichome specific gene expression. ResultsCannabinoid and terpenoid biosynthetic genes, specialised metabolite transporters, and defence related genes, were co-located with distal H3K56ac chromatin, a histone mark that flanks active distal enhancers in planta, exclusively in glandular trichomes. Glandular trichome specific H3K4 trimethylated chromatin was associated with genes involved in specialised metabolism and sucrose and starch metabolism. Bi-valent chromatin loci specific to glandular trichomes, marked with H3K4 trimethylation and H3K27 trimethylation, was associated with genes of MAPK signalling pathways and plant specialised metabolism pathways, supporting recent hypotheses that implicate bi-valent chromatin in plant defence. The histone variant H2A.Z was largely found in intergenic regions and enriched in chromatin that contained genes involved in DNA homeostasis. ConclusionWe report the first genome-wide histone post-translational modification maps for C. sativa glandular trichomes, and more broadly for glandular trichomes in plants. Our findings have implications in plant adaptation and stress response and provide a basis for enhancer-mediated, targeted, gene transformation studies in plant glandular trichomes.

plant biology↗

bioRxiv2021

Insights into opium poppy (Papaver spp.) genetic diversity from genotyping-by-sequencing analysis

Opium poppy (Papaver somniferum) is one of the worlds oldest medicinal plants and a versatile model system to study secondary metabolism. However, our knowledge of its genetic diversity is limited, restricting utilization of the available germplasm for research and crop improvement. We used genotyping-by-sequencing to investigate the extent of genetic diversity and population structure in a collection of poppy germplasm consisting of 91 accessions originating in 30 countries of Europe, North Africa, America, and Asia. We identified five genetically distinct subpopulations using discriminate analysis of principal components and STRUCTURE analysis. Most accessions obtained from the same country were grouped together within subpopulations, likely a consequence of the restriction on movement of poppy germplasm. Alkaloid profiles of accessions were highly diverse, with morphine being dominant. Phylogenetic analysis identified genetic groups that were largely consistent with the subpopulations detected and that could be differentiated broadly based on traits such as number of branches and seed weight. These accessions and the associated genotypic data are valuable resources for further genetic diversity analysis, which could include definition of poppy core sets to facilitate genebank management and use of the diversity for genetic improvement of this valuable crop.

plant biology↗

bioRxiv2017

Gene networks underlying faster flowering induction in response to far-red light

Light is one of the main signals that regulates flowering. Low red to far-red ratios accelerate flowering in a wide range of species. The central gene pathways controlling flowering time in Arabidopsis, appear to be largely conserved in legumes. However, numerous examples exist of gene duplication and loss. The role of CONSTANS-LIKE genes as integrators of the photoperiod response has been questioned in several dicot species, including legumes. In this study on subterranean clover, using RNA-seq and controlled light spectra, we identified 13 differentially expressed genes related to light signalling, meristem identity and flowering promotion. Of these, we pinpointed genes which seem to link photoperiod and far-red light signalling coding for a With no lysine kinase, a CCT motif related to CONSTANS, a FLOWERING LOCUS T b2 like protein, and their active downstream cascade. The earlier down-regulation of these genes under blue compared to far-red-enriched light may explain their role in floral induction. A second independent approach (qPCR analysis) confirmed our findings. Contrasting responses to light quality related to reproduction and defence mechanisms were also found. These results will contribute to a better understanding of the molecular basis of flowering in response to light quality in long-day plants.

genetics↗