Biology subjects

Grativol, C.

Publications and source records attributed to Grativol, C..

5 recordsLinked to original sources

bioRxiv2025

Uncovering the Molecular Regulation of Seed Development and Germination in Endangered Legume Paubrasilia echinata Through Proteomic and Polyamine Analyses

Understanding the molecular regulation of seed maturation and germination is essential for plant conservation and agricultural applications. Here, we provide novel insights into the proteomic and polyamine dynamics of seeds from Paubrasilia echinata, an endangered legume, at 4, 6, and 8 weeks after anthesis. Using a sequential protein extraction approach combined with a species-specific protein database, we identified over 2,000 proteins, uncovering key regulators of maturation, stress tolerance, and germination. Seeds that reached maturity at 6 weeks displayed a high accumulation of proteasome components, translation machinery, and stress-associated proteins, notably late embryogenesis abundant (LEA) and heat shock proteins (HSPs), underscoring their role in seed development. Polyamine profiling showed that high putrescine levels were associated with early development and reduced germination, while spermidine and spermine were correlated with maturation, tolerance to desiccation, and germination. The decreases in certain proteins and polyamines during the transition to germination reveal dynamic regulatory shifts essential for the establishment of seedlings. These molecular signatures reveal dynamic metabolic and regulatory changes that facilitate the transition from seed development to germination. These findings reveal previously uncharacterized mechanisms of seed maturation and early germination in P. echinata and provide information on seed biology, ex situ conservation, and propagation strategies for endangered legumes.

plant biology↗

bioRxiv2020

Altered bacteria community dominance reduces tolerance to resident fungus and seed to seedling growth performance in maize (Zea mays L. var. DBK 177).

Seeds are reservoirs of beneficial and harmful microorganism that modulates plant growth and health. Here, we access seed to seedling bacteriome assembly modified by seed-disinfection and the underlined effect over maize germination performance and root-seedlings microbial colonization. Seed-disinfection was performed with sodium hypochlorite (1.25%, 30 min), resulting in a reduction of the cultivable-dependent fraction of seed-borne bacteria population, but not significantly detected by real-time PCR, microscopy, and biochemical analysis of the roots on germinated seeds. 16S rRNA sequencing revealed that the seed and root bacteriome exhibited similar diversity and did not differ in the structure concerning seed-disinfection. On the other hand, the abundance reduction of the genera f_Enterobacteriaceae_922761 (unassigned genus), Azospirillum, and Acinetobacter in disinfected-seed prior germination seems to display changes in prominence of several new taxa in the roots of germinated seeds. Interestingly, this reduction in the bacteriome negatively affected the germination speed and growth of maize plantlets. Additionally, bacteriome re-shape increased the maize var DKB 177 susceptible to the seed-borne plant pathogen Penicillium sp. Such changes in the natural seed-borne composition removed the natural barrier, increasing susceptibility to pathogens, impairing disinfected seeds to germinate, and develop. We conclude that bacteria borne in seeds modulate the relative abundance of taxa in the root, promote germination, seedling growth, and protect the maize against fungal pathogens.

microbiology↗

bioRxiv2020

Insights into the structure and role of seed-borne bacteriome during maize germination

Seed germination events modulate microbial community composition, which ultimately influences seed to seedling growth performance. Here we assess the seed-borne bacteria community in disinfected and non-disinfected maize seeds and seedlings. Using a gnotobiotic system, sodium hypochlorite (1.25%, 30 min) treated-seeds showed a reduction of bacteria population size and an increase of bacteria community diversity associated with selective suppression of Burkholderia related taxon. The shift in the bacteria community composition in disinfested-seeds negatively affects germination speed, seedling growth, and reserve mobilization rates in comparison with non-disinfected maize seeds. A synthetic bacteria community formed by twelve isolates (9 Burkholderia spp.; 2 Bacillus spp. and 1 Staphylococcus sp.) obtained from natural microbiota of maize seeds herein were capable of recovering germination and seedling growth when reintroduced in disinfected seeds. Overall results showed that changes in bacterial community composition and selective reduction of Burkholderia related members dominance interfere with germination events and initial growth of the maize plantlets. By cultivation-dependent and independent approaches, we deciphered seed-maize microbiome structure, bacterial niches location, and bacterial taxon with relevant roles in seedlings growth performance. A causal relationship between seed microbial community succession and germination performance open opportunities in seed technologies to build-up microbial communities to boost plant growth and health. One sentence summarypartial removal of the seed-borne microbiota negatively affects maize seedling growth performance and altered bacteria community structure. Partial microbial recomposition, mainly with Burkholderia-related isolates, restores the germination phenotype of disinfested seeds.

microbiology↗

bioRxiv2019

Systematic analysis of 1,298 RNA-Seq samples and construction of a comprehensive soybean (Glycine max) expression atlas

Soybean (Glycine max [L.] Merr.) is a major crop in animal feed and human nutrition, mainly for its rich protein and oil contents. The remarkable rise in soybean transcriptome studies over the past five years generated an enormous amount of RNA-seq data, encompassing various tissues, developmental conditions, and genotypes. In this study, we have collected data from 1,298 publicly available soybean transcriptome samples, processed the raw sequencing reads, and mapped them to the soybean reference genome in a systematic fashion. We found that 94% of the annotated genes (52,737/56,044) had detectable expression in at least one sample. Unsupervised clustering revealed three major groups, comprising samples from aerial, underground, and seed/seed-related parts. We found 452 genes with uniform and constant expression levels, supporting their roles as housekeeping genes. On the other hand, 1,349 genes showed heavily biased expression patterns towards particular tissues. A transcript-level analysis revealed that 95% (70,963/74,490) of the known transcripts overlap with those reported here, whereas 3,256 assembled transcripts represent potentially novel splicing isoforms. The dataset compiled here constitute a new resource for the community, which can be downloaded or accessed through a user-friendly web interface at http://venanciogroup.uenf.br/resources/. This comprehensive transcriptome atlas will likely accelerate research on soybean genetics and genomics.

plant biology↗

bioRxiv2017

A Duplication Lost In Sugarcane Hybrids Revealed By Chloroplast Genome Assembly Of Wild Species Saccharum officinarum

Sugarcane is a crop of paramount importance for sustainable energy. Modern sugarcane cultivars are derived from interspecific crosses between the two wild species Saccharum officinarum and Saccharum spontaneum and this event occurred very early in the sugarcane domestication history. This hybridization allowed the generation of cultivars with complex aneuploidy genomes containing 100-130 chromosomes that are unequally inherited - ~80% from S. officinarum, ~10% from S. spontaneum and ~10% from inter-specific crosses. Several studies have highlighted the importance of chloroplast genomes (cpDNA) to investigate hybridization events in plant lineages. Few sugarcane cpDNAs have been assembled and published, including those from sugarcane hybrids. However, cpDNAs of wild Saccharum species remains unexplored. In the present study, we used whole-genome sequencing data to survey the chloroplast genome of the wild sugarcane species S. officinarum. Illumina sequencing technology was used for assembly 142,234 bp of S.officinarum cpDNA with 2,065,893 reads and 1043x of coverage. The analysis of the S. officinarum cpDNA revealed a notable difference in the LSC region of wild and cultivated sugarcanes. Chloroplasts of sugarcane cultivars showed a loss of a duplicated fragment with 1,031 bp in the beginning of the LSC region, which decreased the chloroplast gene content in hybrids. Based on these results, we propose the comparative analysis of organelle genomes as a very important tool for deciphering and understanding hybrid Saccharum lineages.

genomics↗