Biology subjects

Pico, B.

Publications and source records attributed to Pico, B..

4 recordsLinked to original sources

bioRxiv2022

Computer generation of fruit shapes from DNA sequence

The generation of realistic plant and animal images from marker information could be a main contribution of artificial intelligence to genetics and breeding. Since morphological traits are highly variable and highly heritable, this must be possible. However, a suitable algorithm has not been proposed yet. This paper is a proof of concept demonstrating the feasibility of this proposal using decoders, a class of deep learning architecture. We apply it to Cucurbitaceae, perhaps the family harboring the largest variability in fruit shape in the plant kingdom, and to tomato, a species with high morphological diversity also. We generate Cucurbitaceae shapes assuming a hypothetical, but plausible, evolutive path along observed fruit shapes of C. melo. In tomato, we used 353 images from 129 crosses between 25 maternal and 7 paternal lines for which genotype data were available. In both instances, a simple decoder was able to recover expected shapes with large accuracy. For the tomato pedigree, we also show that the algorithm can be trained to generate offspring images from their parents shapes, bypassing genotype information. Data and code are available at https://github.com/miguelperezenciso/dna2image.

bioinformatics↗

bioRxiv2021

Exploring the miRNA-mediated response to combined stresses in melon plants

Climate change has been associated with a higher incidence of combined adverse environmental conditions that can promote a significant decrease in crop productivity. However, knowledge on how a combination of stresses might affect plant development is still scarce. MicroRNAs (miRNAs) have been proposed as potential targets for improving crop-productivity. Here, we have combined deep-sequencing, computational characterization of responsive miRNAs and validation of their regulatory role in a comprehensive analysis of melons response to several combinations of four stresses (cold, salinity, short day, and infection with a fungus). Twenty-two miRNA families responding to double and/or triple stresses were identified. The regulatory role of the differentially expressed miRNAs was validated by quantitative measurements of the expression of the corresponding target genes. A high proportion (ca. 60%) of these families (mainly highly conserved miRNAs targeting transcription factors) showed a non-additive response to multiple stresses in comparison with that observed under each one of the stresses individually. Among those miRNAs showing non-additive response to stress-combinations, most interactions were negative suggesting the existence of functional convergence in the miRNA-mediated response to combined stresses. Taken together, our results provide compelling evidences that the response to combined stresses cannot be easily predicted from the study individual stresses.

plant biology↗

bioRxiv2021

Carotenoid and tocopherol fortification of zucchini fruits using a viral RNA vector

Carotenoids and tocopherols are health-promoting metabolites in livestock and human diets. Some important crops have been genetically modified to increase their content. Although the usefulness of transgenic plants to alleviate nutritional deficiencies is obvious, their social acceptance has been controversial. Here, we demonstrate an alternative biotechnological strategy for carotenoid and tocopherol fortification of edible fruits in which no transgenic DNA is involved. A viral RNA vector derived from Zucchini yellow mosaic virus (ZYMV) was modified to express a bacterial phytoene synthase (crtB), and inoculated in zucchini (Cucurbita pepo L.) leaves nurturing pollinated flowers. After the viral vector moved to the developing fruit and expressed crtB, the rind and flesh of the fruits developed yellow-orange rather than green color. Metabolite analyses showed a substantial enrichment in health-promoting carotenoids, such as - and {beta}-carotene (pro-vitamin A), lutein and phytoene, in both rind and flesh. Considerably higher accumulation of - and {gamma}-tocopherol was also detected, particularly in fruit rind. Although this strategy is perhaps not free from controversy due to the use of genetically modified viral RNA, our work does demonstrate the possibility of metabolically fortifying edible fruits using an approach in which no transgenes are involved.

plant biology↗

bioRxiv2017

De-novo assembly of zucchini genome reveals a whole genome duplication associated with the origin of the Cucurbita genus

The Cucurbita genus (squashes, pumpkins, gourds) includes important domesticated species such as C. pepo, C. maxima and C. moschata. In this study, we present a high-quality draft of the zucchini (C. pepo) genome. The assembly has a size of 263 Mb, a scaffold N50 of 1.8 Mb, 34,240 gene models, includes 92% of the conserved BUSCO core gene set, and it is estimated to cover 93.0% of the genome. The genome is organized in 20 pseudomolecules, that represent 81.4% of the assembly, and it is integrated with a genetic map of 7,718 SNPs. Despite its small genome size three independent evidences support that the C. pepo genome is the result of a Whole Genome Duplication: the topology of the gene family phylogenies, the karyotype organization, and the distribution of 4DTv distances. Additionally, 40 transcriptomes of 12 species of the genus were assembled and analyzed together with all the other published genomes of the Cucurbitaceae family. The duplication was detected in all the Cucurbita species analyzed, including C. maxima and C. moschata, but not in the more distant cucurbits belonging to the Cucumis and Citrullus genera, and it is likely to have happened 30 {+/-} 4 Mya in the ancestral species that gave rise to the genus.

genomics↗