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The predicted sequence for thousands of genes revealed by a preliminary low-coverage genome assembly is presented for Brycon orbignyanus, an endangered migratory fish. Neotropical migratory fish stocks have been drastically reduced due to accumulated environmental pressure. Brycon orbignyanus, once one of the main fisheries species in the Platine Basin, is now very rare in nature and relies on spawning programs and a few well preserved or still untouched sites. The use of high-throughput DNA sequencing is still untapped regarding the functional genome information from B. orbignyanus. In order to help bridging this gap, we present a dataset resulting from the first functional annotation from a de novo genome assembly for B. orbignyanus, from short reads (90 bp), obtained by the HiSeq 2000 platform (Illumina). The annotation was performed for scaffolds over 10 kb using the Maker pipeline, with reference sequences taken from the NCBI for the Characiformes order. This annotation resulted in the prediction of 12,734 genes, classified with the aid of PANTHER. The data presented here can facilitate the development of basic research in this threatened species, along with practical biotechnological tools for different areas, such as commercial and environmental fish spawning operations (e.g. hormonal induction, growth) and human health.

Made available in DSpace on 2021-06-25T11:57:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The Neotropical fish genus Prochilodus includes five species occurring in the main drainages of the eastern Brazilian Shield: P. argenteus, P. costatus, P. lineatus, P. harttii, and P. vimboides. Multi and single locus phylogenies have questioned the monophyly of P. costatus and P. lineatus, and the biogeographic history of these species in the Brazilian Shield has never been explored. We characterized new mitogenomes for these species to reconstruct their evolutionary history, estimated the timing of Prochilodus cladogenesis, and discussed the implications of past geologic events on species diversification. The phylogeny supports the monophyly of both P. costatus and P. lineatus, and indicates a Miocene divergence of P. vimboides, much earlier than subsequent species diversification. The Early Pleistocene split of P. argenteus and P. harttii (similar to 2.1 million years ago-MYA) is hypothesized to be related to recent Quaternary reactivations of the Rio Aracuai Fault that promoted river captures between the eastern tributaries of the Sao Francisco basin and the upper Rio Jequitinhonha in the Serra do Espinhaco mountain range. The time-calibrated phylogeny also indicated a subsequent split of P. costatus and P. lineatus (similar to 1.1 MYA) likely due to Quaternary activities of the Upper Rio Sao Francisco crustal discontinuity and Estrela Fault that catalyzed river captures between the upper Rio Sao Francisco and the Rio Grande of the Parana basin in the Serra da Canastra mountain range. These results provide a temporal context for the diversification of Prochilodus and bring new insights to further study the historical biogeography of other riverine fish groups along the upland basins of the eastern Brazilian Shield. Pontificia Univ Catolica Minas Gerais, Lab Genet Conservacao, Programa Posgrad Biol Vertebrados, Belo Horizonte, MG, Brazil Univ Fed Sao Joao del Rei, Lab Recursos Genet, Programa Posgrad Ecol, Sao Joao Del Rei, Brazil Univ Estadual Paulista, Dept Biol Estrutural & Func, Inst Biociencias, Botucatu, SP, Brazil Univ Fed Sao Joao del Rei, Programa Posgrad Ciencia Comp, Sao Joao Del Rei, Brazil Univ Fed Rio de Janeiro, Inst Bioquim Med Leopoldo Meis, Lab Genom & Biodiversidade, Rio De Janeiro, Brazil Univ Estadual Paulista, Dept Biol Estrutural & Func, Inst Biociencias, Botucatu, SP, Brazil CNPq: 404991/2018-1 FAPESP: 16/11313-8

A broad panel of tens of thousands of microsatellite loci is unveiled for an endangered piracema (i.e. migratory) South American fish, Brycon orbignyanus. Once one of the main fisheries resources in the Platine Basin, it is now almost extinct in nature and focus of intense aquaculture activity. A total of 178.2 million paired-end reads (90 bases long) were obtained through the use of sequencing-by-synthesis (from a primary genomic library of 500 bp DNA fragments) and is made available through NCBI's Sequence Read Archive, SRA accession SRX3350440. Short reads were assembled de novo and screening for perfect microsatellite motifs revealed more than 81 thousands unique microsatellite loci, for which primer pairs were proposed. A total of 29 polymorphic microsatellite markers were already previously validated for this panel. A partial genomic assembly is hereby presented and these genomic resources are publicly made available. These data will foster the rapid development of hundreds of new DNA markers for genetic diversity studies, conservation initiatives and management practices for this important and depleted species. The availability of such preliminary genomic data will also be of use in the areas of bioinformatics, ecology, genetics and evolution.

The objective of this work was to evaluate 41 microsatellite markers for heterologous amplifications in piracanjuba (Brycon orbignyanus). Some markers were tested for the first time. Loci were optimized for PCR conditions and applied to a sample of 49 individuals. Thirty-one loci resulted in PCR product formation, whereas ten loci yielded intelligible polymorphic patterns in the evaluated sample and can be used for amplifications in this species. From the evaluated markers, four loci (BoM1, BoM13, Bh6, and Bh16) are valid to be applied in the study of piracanjuba.

A broad panel of tens of thousands of microsatellite loci is unveiled for an endangered piracema (i.e. migratory) South American fish, Brycon orbignyanus. Once one of the main fisheries resources in the Platine Basin, it is now almost extinct in nature and focus of intense aquaculture activity. A total of 178.2 million paired-end reads (90 bases long) were obtained through the use of sequencing-by-synthesis (from a primary genomic library of 500 bp DNA fragments) and is made available through NCBI’s Sequence Read Archive, SRA accession SRX3350440. Short reads were assembled de novo and screening for perfect microsatellite motifs revealed more than 81 thousands unique microsatellite loci, for which primer pairs were proposed. A total of 29 polymorphic microsatellite markers were already previously validated for this panel. A partial genomic assembly is hereby presented and these genomic resources are publicly made available. These data will foster the rapid development of hundreds of new DNA markers for genetic diversity studies, conservation initiatives and management practices for this important and depleted species. The availability of such preliminary genomic data will also be of use in the areas of bioinformatics, ecology, genetics and evolution.

Bokermmanohyla saxicola is endemic to the Espinhaco Mountain Range (southeastern Brazil), and broadly distributed in montane meadows of the Serra do Cipo. Four microsatellite regions were located through genomic library screening for this frog, two of which were chosen for population structure analyses given their high variability levels (10–11 alleles assayed in 75 tadpoles from five different streams). Overall Fst was 0.056, and the studied demes fitted isolation by distance model expectations, but the increase of Fst values was unrelated to increases in geographic distance, as it would be expected in drift-gene flow equilibrium conditions. Microsatellite markers revealed lack of pairwise genetic differentiation in spatially close demes and also in some distant ones, a pattern that may be caused by the combination of limited migration ability and past event effects contingent upon suitable habitat conditions for frog movement.

The venom of Loxosceles intermedia was investigated for the presence of insecticidal toxins active against Spodoptera frugiperda (Lepdoptera: Noctuidade), an insect that has caused great reductions in corn production in Brazil. A combination of gel filtration (Sephadex G-100) and ion-exchange chromatography (Carboxymethyl Cellulose, CM 52) resulted in four major fractions that were submitted to biological assay. Fraction 4 was further purified by a reverse phase HPLC (C18 Column) resulting in peptides active against Spodoptera frugiperda. Three new potential insecticidal toxins named LiTx x 1, LiTx x 2 and LiTx x 3 were identified. The partial amino terminal sequences of these peptides were obtained and used to clone the corresponding cDNAs with the help of degenerate oligonucleotides. The amino acid sequence deduced from the cDNA of LiTx x 1, LiTx x 2 and LiTx x 3 revealed mature proteins of approximately 7.4, 7.9 and 5.6 kDa.

The first complete mitochondrial genome for the Anostomidae fish family has been announced. Piracema fishes are the potamodromous migratory species from South America, which undergo lengthy and dramatic yearly reproductive upstream runs. The piracema species Leporinus piavussu has recently been described after a long misidentification history. Its mitogenome, assembled using NGS data and Sanger sequencing, consists in a 16,682 bp circular molecule (GenBank accession number KM886569). The exact sequence and position of 37 mitochondrial genes and the control region is established. A possible case of heteroplasmy was found with NGS and corroborated by Sanger sequencing. These results will positively contribute to the debate about this group’s taxonomy, evolution and conservation.

The cursor complex is a group within the Akodon genus of South American rodents, formed by Akodon cursor and A. montensis. Correct distinction between these two species is of great importance since they can harbor different Hantavirus strains. These species are only distinguishable by means of karyotypic or internal anatomic features, requiring dissection; recently, some other genetic methods have become available. We developed RAPD markers capable of distinguishing between A. cursor and A. montensis. Samples included 42 individuals of A. cursor from four localities and 16 individuals of A. montensis from two localities. Fifty-five bands, 41 of which were polymorphic, were analyzed. A principal component analysis showed that this set of markers could successfully distinguish between the two species, mainly based on three RAPD bands. The number of bands in each population was compared within a 95% confidence interval as a measure of intraspecific variability. The A. cursor populations were found to have marked genetic structure across the study area (AMOVA; F(ST )= 0.21), which in part might be because of the relatively limited dispersal capabilities of this species. Species-specific bands, with potential for species identification, were identified.