Roberta Fogliatto Mariot

Selection of reference genes for transcriptional analysis of edible tubers of potato (Solanum tuberosum L.)

Potato (Solanum tuberosum) yield has increased dramatically over the last 50 years and this has been achieved by a combination of improved agronomy and biotechnology efforts. Gene studies are taking place to improve new qualities and develop new cultivars. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) is a bench-marking analytical tool for gene expression analysis, but its accuracy is highly dependent on a reliable normalization strategy of an invariant reference genes. For this reason, the goal of this work was to select and validate reference genes for transcriptional analysis of edible tubers of potato. To do so, RT-qPCR primers were designed for ten genes with relatively stable expression in potato tubers as observed in RNA-Seq experiments. Primers were designed across exon boundaries to avoid genomic DNA contamination. Differences were observed in the ranking of candidate genes identified by geNorm, NormFinder and BestKeeper algorithms. The ranks determined by geNorm and NormFinder were very similar and for all samples the most stable candidates were C2, exocyst complex component sec3 (SEC3) and ATCUL3/ATCUL3A/CUL3/CUL3A (CUL3A). According to BestKeeper, the importin alpha and ubiquitin-associated/ts-n genes were the most stable. Three genes were selected as reference genes for potato edible tubers in RT-qPCR studies. The first one, called C2, was selected in common by NormFinder and geNorm, the second one is SEC3, selected by NormFinder, and the third one is CUL3A, selected by geNorm. Appropriate reference genes identified in this work will help to improve the accuracy of gene expression quantification analyses by taking into account differences that may be observed in RNA quality or reverse transcription efficiency across the samples.

Qualidade sensorial de vinhos tintos finos do Rio Grande do Sul comparados aos importados da Argentina e Chile

This study evaluates the intrinsic quality of red wines from Rio Grande do Sul in comparison with their main competitors from Argentina and Chile. The organoleptic was evaluated by 31 consumers from Porto Alegre - representing the social segment with the upper purchasing power. The test proposed hedonic scales to evaluate the organoleptic attributes of the wines. The statistical analysis was based on the ANOVA and Tukey tests. The results demonstrated that the intrinsic quality perception of red wines produced in Rio Grande do Sul do not restrain the industry competitiveness which can be strengthened by consistent marketing strategies.

Characterization and Transcriptional Profile of Genes Involved in Glycoalkaloid Biosynthesis in New Varieties of Solanum tuberosum L.

Before commercial release, new potato (Solanum tuberosum) varieties must be evaluated for content of toxic compounds such as glycoalkaloids (GAs), which are potent poisons. GA biosynthesis proceeds via the cholesterol pathway to α-chaconine and α-solanine. The goal of this study was to evaluate the relationship between total glycoalkaloid (TGA) content and the expression of GAME, SGT1, and SGT3 genes in potato tubers. TGA content was measured by HPLC-MS, and reverse transcription quantitative polymerase chain reactions were performed to determine the relative expression of GAME, SGT1, and SGT3 genes. We searched for cis-elements of the transcription start site using the PlantPAN database. There was a relationship between TGA content and the relative expression of GAME, SGT1, and SGT3 genes in potato tubers. Putative promoter regions showed the presence of several cis-elements related to biotic and abiotic stresses and light. These findings provide an important step toward understanding TGA regulation and variation in potato tubers.

Complete Genome Sequence of Enterococcus faecalis Strain P8-1 Isolated from Wild Magellanic Penguin (Spheniscus magellanicus) Feces on the South Coast of Brazil.

ABSTRACT Enterococcus faecalis strains have a ubiquitous nature that allows them to survive in different niches. Studies involving enterococci isolated from marine animals are scarce. Therefore, in this study, we report the complete genome sequence of E. faecalis strain P8-1 isolated from feces of a Magellanic penguin on the south coast of Brazil.

Complete Genome Sequences of Two Listeria monocytogenes Serovars, 1/2a and 4b, Isolated from Dairy Products in Brazil

ABSTRACT Listeria monocytogenes is the foodborne pathogen responsible for a bacterial infection called listeriosis. Here, we present the whole-genome sequences of two L. monocytogenes serovars, 1/2a and 4b, which are considered the most prevalent in food processing plants and listeriosis outbreaks, respectively.

13-loci STR multiplex system for Brazilian seized samples of marijuana: individualization and origin differentiation

It is known that Cannabis in Brazil could either originate from Paraguay or be cultivated in Brazil. While consumer markets in the North and Northeast regions are maintained by national production, the rest of the country is supplied with Cannabis from Paraguay. However, the Brazilian Federal Police (BFP) has exponentially increased the seizure number of Cannabis seeds sent by mail. For this reason, the aim of the study was to assess the 13-loci short tandem repeat (STR) multiplex system proposed by Houston et al. (2015) to evaluate the power of such markers in individualization and origin differentiation of Cannabis sativa samples seized in Brazil by the BFP. To do so, 72 Cannabis samples seized in Brazil by BFP were analyzed. The principal coordinate analysis (PCoA) and probability identity (PI) analysis were computed. Additionally, the Cannabis samples’ genotypes were subjected to comparison by Kruskal-Wallis H, followed by a multiple discriminant analysis (MDA). All samples analyzed revealed a distinct genetic profile. PCoA clearly discriminated the seizure sets based on their geographic origin. A combination of seven loci was enough to differentiate samples’ genotypes, and the PI for a random sample is approximately one in 50 billion. The Cannabis samples were 100% correct as classified by Kruskal-Wallis H, followed by an MDA. The results of this study demonstrate that the 13-loci STR multiplex system successfully achieved the aim of sample individualization and origin differentiation and suggest that it could be a useful tool to help BFP intelligence in tracing back-trade routes.