Biology subjects

Rollano-Penaloza, O. M.

Publications and source records attributed to Rollano-Penaloza, O. M..

5 recordsLinked to original sources

bioRxiv2022

Acai (Euterpe precatoria Mart. Arecaceae) from the Northern Region of Bolivia is not contaminated with Trypanosoma cruzi

Chagas disease is a very important public health problem in America. It is caused by the protozoan parasite Trypanosoma cruzi and transmitted by vectors such as Triatomine insects. However, oral transmission is generating more T. cruzi infections than vectorial transmission in Brazilian Amazonic regions, probably due to the increased consumption of tropical fruits such as acai. Acai palms have become very popular due to its good nutritional properties. Acai fruits have different sources depending of their geographical origin. Acai palms (Euterpe oleracea) in Brazil are cultivated, while in Bolivia grow in wild populations and belongs to a different species, the solitary acai (Euterpe precatoria). Only acai from Brazil has been involved in T. cruzi oral transmission, while Bolivian acai has been regarded as disease free. In order to verify the absence of T. cruzi on acai products from Bolivia, we developed a method to detect T. cruzi DNA by real-Time PCR with internal controls for solitary acai. In this study we show that acai good manufacturing process did not interfere with the detection of acai or T. cruzi DNA. Finally, we report that freshly collected acai fruits and acai frozen pulps from Bolivia were not contaminated with T. cruzi.

ecology↗

bioRxiv2021

SARS-CoV-2 genome sequencing with Oxford Nanopore Technology and Rapid PCR Barcoding in Bolivia

SARS-CoV-2 genomic surveillance has Illumina technology as the golden standard. However, Oxford Nanopore Technology (ONT) provides significant improvements in accessibility, turnaround time and portability. Characteristics that gives developing countries the opportunity to perform genome surveillance. The most used protocol to sequence SARS-CoV-2 with ONT is an amplicon-sequencing protocol provided by the ARTIC Network which requires DNA ligation. Ligation reagents can be difficult to obtain in countries like Bolivia. Thus, here we provide an alternative for library preparation using the rapid PCR barcoding kit (ONT). We mapped more than 3.9 million sequence reads that allowed us to sequence twelve SARS-CoV-2 genomes from three different Bolivian cities. The average sequencing depth was 324X and the average genome length was 29527 bp. Thus, we could cover in average a 98,7% of the reference genome. The twelve genomes were successfully assigned to four different nextstrain clades (20A, 20B, 20E and 20G) and we could observe two main lineages of SARS-CoV-2 circulating in Bolivia. Therefore, this alternative library preparation for SARS-CoV-2 genome sequencing is effective to identify SARS-CoV-2 variants with high accuracy and without the need of DNA ligation. Hence, providing another tool to perform SARS-CoV-2 genome surveillance in developing countries.

genomics↗

bioRxiv2021

Whole Chloroplast Genomes reveals the uniqueness of Bolivian native cacao (Theobroma cacao) from the northern part of Bolivia

We report the complete chloroplast sequences of two varieties of Theobroma cacao collected in the Bolivian Amazonia using Next-Generation Sequencing. Comparisons made between these two chloroplast genomes and the Belizean reference plastid genome identified 19 and 22 nucleotide variants. The phylogenetic analysis reported three main T. cacao clades belonging to the Forastero, Criollo and Trinitario groups. The Bolivian Native Cacao varieties were located inside the Trinitario group forming their unique branch. The Bolivian Native Cacao branch reveals a possible new subpopulation different from the well-characterized T. cacao subpopulations. The phylogenetic trees showed that the relationships among the T. cacao varieties were consistent with their geographical locations placing the Cacao Center of Origin in Western Amazon. The data presented here will contribute to the usage of ultrabarcoding to distinguish different T. cacao varieties and to identify native cacaos from introduced cacaos. Thus helping in the conservation of local native varieties of T. cacao.

plant biology↗

bioRxiv2021

Transcriptomic analysis of quinoa reveals a group of germin-like proteins induced by Trichoderma

Symbiotic strains of fungi in the genus Trichoderma affect growth and pathogen resistance of many plant species, but the interaction is not known in molecular detail. Here we describe the transcriptomic response of two cultivars of the crop Chenopodium quinoa to axenic co-cultivation with Trichoderma harzianum BOL-12 and Trichoderma afroharzianum T22. The response of C. quinoa roots to BOL-12 and T22 in the early phases of interaction was studied by RNA sequencing and RT-qPCR verification. Interaction with the two fungal strains induced partially overlapping gene expression responses. Comparing the two plant genotypes, a broad spectrum of putative quinoa defense genes were found activated in the cultivar Kurmi but not in the Real cultivar. In cultivar Kurmi, relatively small effects were observed for classical pathogen response pathways but instead a C. quinoa-specific clade of germin-like genes were activated. Germin-like genes were found to be more rapidly induced in cultivar Kurmi as compared to Real. The same germin-like genes were found to also be upregulated systemically in the leaves. No strong correlation was observed between any of the known hormone-mediated defense response pathways and any of the quinoa-Trichoderma interactions. The differences in responses are relevant for the capabilities of applying Trichoderma agents for crop protection of different cultivars of C. quinoa.

genomics↗

bioRxiv2019

The disease progression and molecular defense response in Chenopodium quinoa infected with Peronospora variabilis, the causal agent of quinoa downy mildew

The downy mildew disease, caused by the biotrophic oomycete Peronospora variabilis, is the largest environmental threat to quinoa (Chenopodium quinoa Willd.) cultivation in the Andean highlands. However, so far no molecular information on the quinoa-Peronospora interaction has been reported. Here, we have developed tools to study the downy mildew disease in quinoa at gene expression level. Living P. variabilis could be isolated and maintained in the presence of a fungicide, allowing the characterization of downy mildew disease progression in two differently susceptible quinoa cultivars under controlled conditions. Quinoa gene expression changes induced by P. variabilis were analysed by qRT-PCR for quinoa homologues of Arabidopsis thaliana pathogen-associated genes. Overall, we observed a slower disease progression and higher tolerance in the quinoa cultivar Kurmi than in the cultivar Maniquena Real. We also observed that quinoa orthologs of A. thaliana genes involved in the salicylic acid defense response pathway (AtCAT2 and AtEP3) did not have changes in its gene expression. In contrast, quinoa orthologs of A. thaliana gene markers of the induction of the jasmonic acid response pathway (AtWRKY33 and AtHSP90) were significantly induced in plants infected with P. variabilis. These genes could be used as defense response markers to select quinoa cultivars that are more tolerant to P. variabilis infection.

plant biology↗