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Understanding the evolution and the effect of plasticity in plant responses to environmental changes is crucial to combat global climate change. It is particularly interesting in species that survive in distinct environments, such as Eugenia uniflora, which thrives in contrasting ecosystems within the Atlantic Forest (AF). In this study, we combined transcriptome analyses of plants growing in nature (Restinga and Riparian Forest) with greenhouse experiments to unveil the DEGs within and among adaptively divergent populations of E. uniflora. We compared global gene expression among plants from two distinct ecological niches. We found many differentially expressed genes between the two populations in natural and greenhouse-cultivated environments. The changes in how genes are expressed may be related to the species' ability to adapt to specific environmental conditions. The main difference in gene expression was observed when plants from Restinga were compared with their offspring cultivated in greenhouses, suggesting that there are distinct selection pressures underlying the local environmental and ecological factors of each Restinga and Riparian Forest ecosystem. Many of these genes engage in the stress response, such as water and nutrient transport, temperature, light intensity, and gene regulation. The stress-responsive genes we found are potential genes for selection in these populations. These findings revealed the adaptive potential of E. uniflora and contributed to our understanding of the role of gene expression reprogramming in plant evolution and niche adaptation. [ABSTRACT FROM AUTHOR]

Strawberry (Fragaria ananassa Duch.) is an economically important fruit with a high demand owing to its good taste and medicinal properties. However, its cultivation is affected by various biotic and abiotic stresses. Plants exhibit several intrinsic mechanisms to deal with stresses. In the case of strawberry, the mechanisms highlighting the response against these stresses remain to be elucidated, which has hampered the efforts to develop and cultivate strawberry plants with high yield and quality. Although a virtual reference genome of F. ananassa has recently been published, there is still a lack of information on the expression of genes in response to various stresses. Therefore, to provide molecular information for further studies with strawberry plants, we present the reference transcriptome dataset of F. ananassa, assembled and annotated from deep RNA‐Seq data of fruits cultivated under salinity and drought stresses. We also systematically arranged a series of transcripts differentially expressed during these stresses, with an emphasis on genes related to the accumulation of ascorbic acid (AsA). Ascorbic acid is the most potent antioxidant present in these fruits and highly considered during biofortification. A comparison of the expression profile of these genes by RT‐qPCR with the content of AsA in the fruits verified a tight regulation and balance between the expression of genes, from biosynthesis, degradation and recycling pathways, resulting in the reduced content of AsA in fruits under these stresses. These results provide a useful repertoire of genes for metabolic engineering, thereby improving the tolerance to stresses. [ABSTRACT FROM AUTHOR]

Key message: We have elucidated the Andigena origin of the potato Ryadg gene on chromosome XI of CIP breeding lines and developed two marker assays to facilitate its introgression in potato by marker-assisted selection.Abstract: Potato virus Y (PVY) is causing yield and quality losses forcing farmers to renew periodically their seeds from clean stocks. Two loci for extreme resistance to PVY, one on chromosome XI and the other on XII, have been identified and used in breeding. The latter corresponds to a well-known source of resistance (Solanum stoloniferum), whereas the one on chromosome XI was reported from S. stoloniferum and S. tuberosum group Andigena as well. To elucidate its taxonomic origin in our breeding lines, we analyzed the nucleotide sequences of tightly linked markers (M45, M6) and screened 251 landraces of S. tuberosum group Andigena for the presence of this gene. Our results indicate that the PVY resistance allele on chromosome XI in our breeding lines originated from S. tuberosum group Andigena. We have developed two marker assays to accelerate the introgression of Ryadg gene into breeding lines by marker-assisted selection (MAS). First, we have multiplexed RYSC3, M6 and M45 DNA markers flanking the Ryadg gene and validated it on potato varieties with known presence/absence of the Ryadg gene and a progeny of 6,521 individuals. Secondly, we developed an allele-dosage assay particularly useful to identify multiplex Ryadg progenitors. The assay based on high-resolution melting analysis at the M6 marker confirmed Ryadg plex level as nulliplex, simplex and duplex progenitors and few triplex progenies. These marker assays have been validated and can be used to facilitate MAS in potato breeding. [ABSTRACT FROM AUTHOR]

The globalization and increasing ease of Internet access allow more people to share content than ever before. A substantial amount of this content relates to another's copyrighted material, whether it is infringing content such as piracy or noninfringing content such as commentaries, criticisms, parodies, or other material falling under fair use. Due in part to piracy concerns, the Online Copyright Infringement Liability Limitation Act (OCILLA) created a process meant to expedite removal of infringing content hosted on the Internet. However, this takedown process has been used to remove noninfringing content that uses another's copyright material, but falling under fair use. This usage of the takedown process is enabled by the requirement that the original copyright owner only needs a good faith belief that the target's use is not authorized, and by the nature of fair use determination--the consideration of various factors--which makes determinations of individual works difficult. Due to this difficulty, copyright owners are able to easily meet the good faith standard, endangering fair use speech on the Internet. Therefore OCILLA needs to change in order to decrease the chilling effect on this type of speech. Proposals have been made to ameliorate this situation. However, most of them overreach and impede copyright owners from expeditious removal of clearly infringing material, contrary to the purpose of OCILLA. This comment suggests a different solution: creation of safe harbor provisions where certain narrow categories of content are irrebuttably presumed to be fair use. Though this solution does not alleviate the problem on fair use content in general, it allows for greater certainty to people who want to create content based on another's work while qualifying as fair use, without obstructing copyright owners from protecting their works through removing infringing material. [ABSTRACT FROM AUTHOR]

MicroRNAs, or miRNAs, are endogenously encoded small RNAs that play a key role in diverse plant biological processes. Jatropha curcas L. has received significant attention as a potential oilseed crop for the production of renewable oil. Here, a sRNA library of mature seeds and three mRNA libraries from three different seed development stages were generated by deep sequencing to identify and characterize the miRNAs and pre-miRNAs of J. curcas. Computational analysis was used for the identification of 180 conserved miRNAs and 41 precursors (pre-miRNAs) as well as 16 novel pre-miRNAs. The predicted miRNA target genes are involved in a broad range of physiological functions, including cellular structure, nuclear function, translation, transport, hormone synthesis, defense, and lipid metabolism. Some pre-miRNA and miRNA targets vary in abundance between the three stages of seed development. A search for sequences that produce siRNA was performed, and the results indicated that J. curcas siRNAs play a role in nuclear functions, transport, catalytic processes and disease resistance. This study presents the first large scale identification of J. curcas miRNAs and their targets in mature seeds based on deep sequencing, and it contributes to a functional understanding of these miRNAs. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is the world's most important non-grain food crop and is central to global food security. It is clonally propagated, highly heterozygous, autotetraploid, and suffers acute inbreeding depression. Here we use a homozygous doubled-monoploid potato clone to sequence and assemble 86% of the 844-megabase genome. We predict 39,031 protein-coding genes and present evidence for at least two genome duplication events indicative of a palaeopolyploid origin. As the first genome sequence of an asterid, the potato genome reveals 2,642 genes specific to this large angiosperm clade. We also sequenced a heterozygous diploid clone and show that gene presence/absence variants and other potentially deleterious mutations occur frequently and are a likely cause of inbreeding depression. Gene family expansion, tissue-specific expression and recruitment of genes to new pathways contributed to the evolution of tuber development. The potato genome sequence provides a platform for genetic improvement of this vital crop. [ABSTRACT FROM AUTHOR]