Somatic Embryogenesis and -Mediated Gene Transfer Procedures in Chilean Temperate Japonica Rice Varieties for Precision Breeding.

Rice () varieties are generated through breeding programs focused on local requirements. In Chile, the southernmost rice producer, rice productivity relies on the use and generation of temperate japonica germplasms, which need to be adapted to the intensifying effects of climate change. Advanced biotechnological tools can contribute to these breeding programs; new technologies associated with precision breeding, including gene editing, rely on procedures such as regeneration and gene transfer.

Small RNA Differential Expression Analysis Reveals miRNAs Involved in Dormancy Progression in Sweet Cherry Floral Buds.

In sweet cherry (), as in other temperate woody perennials, bud dormancy allows for survival in adverse environmental conditions during winter. During this process, environmental signals such as short days and/or low temperatures trigger internal signals that enable buds to become tolerant to the cold. The process involves tracking chilling units up to chilling the requirement fulfillment to resume growth, a transition involving transcriptional regulation, metabolic signaling, and epigenetic-related regulatory events.

CRISPR/Cas9 Targeted Editing of Genes Associated With Fungal Susceptibility in L. cv. Thompson Seedless Using Geminivirus-Derived Replicons.

The woody nature of grapevine ( L.) has hindered the development of efficient gene editing strategies to improve this species. The lack of highly efficient gene transfer techniques, which, furthermore, are applied in multicellular explants such as somatic embryos, are additional technical handicaps to gene editing in the vine.

A Traceable DNA-Replicon Derived Vector to Speed Up Gene Editing in Potato: Interrupting Genes Related to Undesirable Postharvest Tuber Traits as an Example.

In potato ( L.), protoplast techniques are limited to a few genotypes; thus, the use of regular regeneration procedures of multicellular explants causes us to face complexities associated to CRISPR/Cas9 gene editing efficiency and final identification of individuals. Geminivirus-based replicons contained in T-DNAs could provide an improvement to these procedures considering their cargo capability.

and Induce a Differential MicroRNA Profile in Human Placental Explants.

and are two parasites than can be transmitted from mother to child through the placenta. However, congenital transmission rates are low for and high for . Infection success or failure depends on complex parasite-host interactions in which parasites can alter host gene expression by modulating non-coding RNAs such as miRNAs.

Physicochemical Parameters Affecting the Distribution and Diversity of the Water Column Microbial Community in the High-Altitude Andean Lake System of La Brava and La Punta.

Due to the low incidence of precipitation attributed to climate change, many high-altitude Andean lakes (HAALs) and lagoons distributed along the central Andes in South America may soon disappear. This includes La Brava-La Punta, a brackish lake system located south of the Salar de Atacama within a hyper-arid and halophytic biome in the Atacama Desert. Variations in the physicochemical parameters of the water column can induce changes in microbial community composition, which we aimed to determine.

Genetic Transformation in Peach ( L.): Challenges and Ways Forward.

Almost 30 years have passed since the first publication reporting regeneration of transformed peach plants. Nevertheless, the general applicability of genetic transformation of this species has not yet been established. Many strategies have been tested in order to obtain an efficient peach transformation system.

Silencing of one copy of the translation initiation factor eIFiso4G in Japanese plum (Prunus salicina) impacts susceptibility to Plum pox virus (PPV) and small RNA production.

Background: In plants, host factors encoded by susceptibility (S) genes are indispensable for viral infection. Resistance is achieved through the impairment or the absence of those susceptibility factors. Many S genes have been cloned from model and crop species and a majority of them are coding for members of the eukaryotic translation initiation complex, mainly eIF4E, eIF4G and their isoforms.

genetics and applications after de novo genome sequencing: achievements and prospects.

Prior to the availability of whole-genome sequences, our understanding of the structural and functional aspects of tree genomes was limited mostly to molecular genetic mapping of important traits and development of EST resources. With public release of the peach genome and others that followed, significant advances in our knowledge of genomes and the genetic underpinnings of important traits ensued. In this review, we highlight key achievements in genetics and breeding driven by the availability of these whole-genome sequences.

-Mediated Transformation of Tree Fruit Crops: Methods, Progress, and Challenges.

Genetic engineering based on -mediated transformation has been a desirable tool to manipulate single or multiple genes of existing genotypes of woody fruit crops, for which conventional breeding is a difficult and lengthy process due to heterozygosity, sexual incompatibility, juvenility, or a lack of natural sources. To date, successful transformation has been reported for many fruit crops. We review the major progress in genetic transformation of these fruit crops made in the past 5 years, emphasizing reproducible transformation protocols as well as the strategies that have been tested in fruit crops.

A comparison of the EU regulatory approach to directed mutagenesis with that of other jurisdictions, consequences for international trade and potential steps forward.

A special regulatory regime applies to products of recombinant nucleic acid modifications. A ruling from the European Court of Justice has interpreted this regulatory regime in a way that it also applies to emerging mutagenesis techniques. Elsewhere regulatory progress is also ongoing.

ABA Represses the Expression of Cell Cycle Genes and May Modulate the Development of Endodormancy in Grapevine Buds.

Recently, the plant hormone abscisic acid (ABA) has been implicated as a key player in the regulation of endodormancy (ED) in grapevine buds ( L). In this study, we show that in the vine, the expression of genes related to the biosynthesis of ABA () and the content of ABA are significantly higher in the latent bud than at the shoot apex, while the expression of an ABA catabolic gene () showed no significant difference between either organ. A negative correlation between the content of ABA and transcript levels of cell cycle genes (CCG) was found in both tissues.

DNA methylation and small interference RNAs participate in the regulation of MADS-box genes involved in dormancy in sweet cherry (Prunus avium L.).

Epigenetic modifications can yield information about connections between genotype, phenotype variation and environmental conditions. Bud dormancy release in temperate perennial fruit trees depends on internal and environmental signals such as cold accumulation and photoperiod. Previous investigations have noted the participation of epigenetic mechanisms in the control of this physiological process.

An Internet-based platform for the estimation of outcrossing potential between cultivated and Chilean vascular plants.

A national-scale study of outcrossing potential within Chilean vascular flora was conducted using an upgraded algorithm, which adds parameters such as pollinator agents, climate, and geographic conditions. Datasets were organized and linked in a Web platform (www.flujogenico.

Candidate nematicidal proteins in a new Pseudomonas veronii isolate identified by its antagonistic properties against Xiphinema index.

The nematode Xiphinema index affects grape vines and transmits important viruses associated with fanleaf degeneration. Pseudomonas spp. are an extensive bacterial group in which important biodegradation and/or biocontrol properties can occur for several strains in the group.

A draft genome sequence of R4: a grapevine ( L.) root-associated strain with high biocontrol potential.

A new plant commensal isolate (strain R4) was identified from a biocontrol screen. Isolated from grapevine roots from vineyards in central Chile, the strain R4 exhibited a slower yet equivalently effective nematicide activity as the well-characterized CHA0. Whole genome sequencing of strain R4 and comparative analysis among the available spp.

Synthesis of an artificial Vitis vinifera miRNA 319e using overlapping long primers and its application for gene silencing.

The conserved mechanism of action of micro-RNAs (miRNAs) as regulators of gene expression has allowed the use of artificial miRNAs (amiRNAs) as a powerful tool for candidate gene evaluation in plants. Based on the use of a Vitis vinifera miRNA molecule (i.e.

Outcrossing potential between 11 important genetically modified crops and the Chilean vascular flora.

The potential impact of genetically modified (GM) crops on biodiversity is one of the main concerns in an environmental risk assessment (ERA). The likelihood of outcrossing and pollen-mediated gene flow from GM crops and non-GM crops are explained by the same principles and depend primarily on the biology of the species. We conducted a national-scale study of the likelihood of outcrossing between 11 GM crops and vascular plants in Chile by use of a systematized database that included cultivated, introduced and native plant species in Chile.

Comparative study of two table grape varieties with contrasting texture during cold storage.

Postharvest softening of grape berries is one of the main problems affecting grape quality during export. Cell wall disassembly, especially of pectin polysaccharides, has been commonly related to fruit softening, but its influence has been poorly studied in grapes during postharvest life. In order to better understand this process, the Thompson seedless (TS) variety, which has significantly decreased berry texture after prolonged cold storage, was compared to NN107, a new table grape variety with higher berry firmness.

Genetically engineered Thompson Seedless grapevine plants designed for fungal tolerance: selection and characterization of the best performing individuals in a field trial.

The fungi Botrytis cinerea and Erysiphe necator are responsible for gray mold and powdery mildew diseases, respectively, which are among the most devastating diseases of grapes. Two endochitinase (ech42 and ech33) genes and one N-acetyl-β-D-hexosaminidase (nag70) gene from biocontrol agents related to Trichoderma spp. were used to develop a set of 103 genetically modified (GM) 'Thompson Seedless' lines (568 plants) that were established in open field in 2004 and evaluated for fungal tolerance starting in 2006.

Expression of an optimized Argopecten purpuratus antimicrobial peptide in E. coli and evaluation of the purified recombinant protein by in vitro challenges against important plant fungi.

Antimicrobial peptides (AMP) have been widely described in several organisms from different kingdoms. We recently designed and evaluated a synthetic version of an AMP isolated and characterized from Argopecten purpuratus hemocytes. This study describes the generation of a chimaeric gene encoding for Ap-S, the use of this construct to transform E.

Development of grapevine somatic embryogenesis using an air-lift bioreactor as an efficient tool in the generation of transgenic plants.

The grapevine genetic transformation programs have relayed on the use of solid media-based somatic embryogenesis. To reach a high throughput of candidate gene evaluation in 'Thompson Seedless', a semi-automatic system allowing viable transformation of explants was designed. An intermediate procedure using liquid media and agitated flasks was first characterized, leading to reduction in the biomass duplication time of pro-embryogenic (PE) cells from 30 d in dishes to 14 d.