Base-calling of automated sequencer traces using phred. I. Accuracy assessment

Molecular detection of vector-borne agents in water buffaloes (Bubalus bubalis) and associated ectoparasites from Brazil

Brazil has the largest buffalo herd outside the Asian continent, with more than 1.5 million head. As buffalo farming has become an economically important activity, studies on the occurrence of pathogens shared between cattle and buffalo are necessary. The aim of this study was to investigate the molecular occurrence of piroplasmids and bacterial agents (Anaplasmataceae and Coxiellaceae) potentially transmitted by vectors in buffaloes in southeastern Brazil using molecular methods. DNA was extracted from blood samples of 81 buffaloes, 165 Rhipicephalus microplus ticks, and 92 Haematopinus tuberculatus lice collected from buffaloes in the municipality of Passos, state of Minas Gerais, Brazil. These samples were subjected to conventional PCR (cPCR) assays based on three endogenous genes, namely gapdh from mammals, 16S rRNA from ticks, and cox-1 from lice. Positive samples from these PCR assays were then submitted to a real-time PCR (qPCR) assay targeting IS1111 of Coxiella burnetii, cPCR for Ehrlichia spp. (dsb gene), and nested-PCR assays targeting the 18S rRNA gene of Piroplasmida, sbp-2 of Babesia bovis, and rap-1α of Babesia bigemina. All buffalo and ectoparasite DNA samples tested positive in the PCR assays for the endogenous genes. All samples were negative in the qPCR for C. burnetii and nested PCR for B. bigemina (rap-1α). For Ehrlichia spp., 6/257 (2.3%) ectoparasites (five ticks and one louse) tested positive, with BLASTn analysis showing 88.04% to 100% identity with Ehrlichia minasensis. In the nPCR for piroplasmids (18S rRNA), 8/81 (9.9%) buffaloes and one tick (0.7%) tested positive, with BLASTn analysis showing > 99.9% identity with B. bovis and B. bigemina. In the nPCR for B. bovis (sbp-2), 1/81 buffalo (1.2%) was positive. This study demonstrated, for the first time, the occurrence and co-infection of tick-borne hemoparasites in buffaloes and associated ectoparasites in southeastern Brazil. The lack of positivity for E. minasensis and low molecular occurrence for B. bovis and B. bigemina among buffaloes sampled may be associated with the higher resistance of this ruminant species to R. microplus ticks and vectored pathogens.

Molecular Evidence of Bartonella spp. in Sand Flies (Diptera: Psychodidae) from the Brazilian Amazon

Bartonellosis refers to a group of diseases caused by alpha-proteobacteria from the genus Bartonella, which are typically vector-borne pathogens responsible for emerging and reemerging infections in humans and animals. The transmission of Bartonella has primarily been associated with a wide variety of hematophagous arthropods, including sand flies. The present study aimed to investigate the presence of Bartonella spp. DNA in 297 non-engorged female sand fly specimens (Diptera: Psychodidae) collected in the Amazonian National Park, state of Pará, Brazil. We documented a 12.6% (32/253) infection rate of Bartonella spp. among the sampled sand flies, using a quantitative real-time PCR targeting the 16S-23S rRNA internal transcribed spacer (ITS) region. Further molecular characterization was performed using conventional PCR assays targeting seven molecular markers (rpoB, ribC, nuoG, pap-31, groEL, gltA, and ftsZ). Phylogenetic inference grouped the two Bartonella spp. gltA sequences, detected in Psychodopygus llanosmartinsi and Psychodopygus series Chagasi, in the same clade as Bartonella ancashensis, Bartonella bacilliformis, and ancient lineages of Bartonella spp. previously detected in sand flies from Mexico and Brazil. The role of phlebotomine sand flies in the transmission of Bartonella spp. among bats and the zoonotic potential of the detected genotypes nested in B. ancashensis/B. bacilliformis clade should be further investigated.

Characterization of the complete mitochondrial genomes of two sea cucumbers, Deima validum and Oneirophanta mutabilis (Holothuroidea, Synallactida, Deimatidae): Insight into deep-sea adaptive evolution of Deimatidae

The deep-sea is the largest and most extensive ecosystem on our planet with limited food availability, extreme pressure reaching hundreds of bars, perpetual darkness, frigid temperatures, and minimal oxygen levels. Mitochondria plays a key role in energy metabolism and oxygen usage, thus it may undergo adaptive evolution in response to pressures from extreme harsh environments. In this study, we present the mitochondrial genome sequences of the sea cucumbers Deima validum and Oneirophanta mutabilis collected from the South China Sea. To our knowledge, they are the first reported mitogenomes from the family Deimatidae. Similar to other sea cucumbers, both mitogenomes contain 13 PCGs, 2 rRNA genes, 22 tRNA genes (including duplication of trnS and trnL) and 1 non-coding regions. The genes in both species are distributed on the positive and negative strands, with six genes encoded on the L-strand and 31 genes encoded on the H-strand. We compared the order of genes from the 13 available holothurian mitogenomes and found a novel gene arrangement in D. validum. Phylogenetic analysis revealed that D. validum clustered with O. mutabilis, forming the deep-sea Deimatidae clade. The analysis of individual genes revealed the presence of three sites (90 L, 147 S, 192 V) in nad2 and one site (28 S) in nad5 with high posterior probabilities indicating positive selection. By comparing these features with those of shallow sea cucumbers, we predict that nad2 and nad5 may provide valuable insights into the molecular mechanisms at the mitochondrial level involved in Deimatidae's adaptation to the deep-sea habitat.

De novo clustering of large long-read transcriptome datasets with isONclust3

MOTIVATION

Long-read sequencing techniques can sequence transcripts from end to end, greatly improving our ability to study the transcription process. Although there are several well-established tools for long-read transcriptome analysis, most are reference-based. This limits the analysis of organisms without high-quality reference genomes and samples or genes with high variability (e.g. cancer samples or some gene families). In such settings, analysis using a reference-free method is favorable. The computational problem of clustering long reads by region of common origin is well-established for reference-free transcriptome analysis pipelines. Such clustering enables large datasets to be split roughly by gene family and, therefore, an independent analysis of each cluster. There exist tools for this. However, none of those tools can efficiently process the large amount of reads that are now generated by long-read sequencing technologies.

RESULTS

We present isONclust3, an improved algorithm over isONclust and isONclust2, to cluster massive long-read transcriptome datasets into gene families. Like isONclust, isONclust3 represents each cluster with a set of minimizers. However, unlike other approaches, isONclust3 dynamically updates the cluster representation during clustering by adding high-confidence minimizers from new reads assigned to the cluster and employs an iterative cluster-merging step. We show that isONclust3 yields results with higher or comparable quality to state-of-the-art algorithms but is 10-100 times faster on large datasets. Also, using a 256 Gb computing node, isONclust3 was the only tool that could cluster 37 million PacBio reads, which is a typical throughput of the recent PacBio Revio sequencing machine.

AVAILABILITY AND IMPLEMENTATION

https://github.com/aljpetri/isONclust3.

Robust discrimination between closely related species of salmon based on DNA fragments

Closely related species of Salmonidae, including Pacific and Atlantic salmon, can be distinguished from one another based on nucleotide sequences from the cytochrome c oxidase sub-unit 1 mitochondrial gene (COI), using ensembles of fragments aligned to genetic barcodes that serve as digital proxies for the relevant species. This is accomplished by exploiting both the nucleotide sequences and their quality scores recorded in a FASTQ file obtained via Next Generation (NextGen) Sequencing of mitochondrial DNA extracted from Coho salmon caught with hook and line in the Gulf of Alaska. The alignment is done using MUSCLE (Muscle 5.2) [1], applied to multiple versions of each fragment perturbed according to the nucleobase identification error probabilities underlying the quality scores. The Damerau-Levenshtein distance was used to determine the genetic barcode of the candidate species that is closest to each aligned, perturbed fragment. The "votes" that the sampled fragments cast for the different candidate species are then pooled and converted into identification probabilities, using weights determined by the entropy of the fragment-specific identification probability distributions. This novel approach to quantify the uncertainty associated with measurements made using NextGen Sequencing can be applied to discriminate closely related species, hence to value-assignment for reference materials supporting determinations of the authenticity of seafood, for example, NIST Reference Materials 8256 and 8257 (Coho salmon) [2].

Barcode-free multiplex plasmid sequencing using Bayesian analysis and nanopore sequencing

Plasmid construction is central to life science research, and sequence verification is arguably its costliest step. Long-read sequencing has emerged as a competitor to Sanger sequencing, with the principal benefit that whole plasmids can be sequenced in a single run. Nevertheless, the current cost of nanopore sequencing is still prohibitive for routine sequencing during plasmid construction. We develop a computational approach termed Simple Algorithm for Very Efficient Multiplexing of Oxford Nanopore Experiments for You (SAVEMONEY) that guides researchers to mix multiple plasmids and subsequently computationally de-mixes the resultant sequences. SAVEMONEY defines optimal mixtures in a pre-survey step, and following sequencing, executes a post-analysis workflow involving sequence classification, alignment, and consensus determination. By using Bayesian analysis with prior probability of expected plasmid construction error rate, high-confidence sequences can be obtained for each plasmid in the mixture. Plasmids differing by as little as two bases can be mixed as a single sample for nanopore sequencing, and routine multiplexing of even six plasmids per 180 reads can still maintain high accuracy of consensus sequencing. SAVEMONEY should further democratize whole-plasmid sequencing by nanopore and related technologies, driving down the effective cost of whole-plasmid sequencing to lower than that of a single Sanger sequencing run.

Gut microbiota and metabolome signatures in obese and normal-weight patients with colorectal tumors

Here, we aim to improve our understanding of various colorectal cancer (CRC) risk factors (obesity, unhealthy diet, and gut microbiota/metabolome alteration), analyzing 120 patients with colon polyps, divided in normal-weight (NW) or overweight/obese (OB). Dietary habits data (validated EPIC questionnaires) revealed a higher consumption of processed meat among OB vs. NW patients. Both mucosa-associated microbiota (MAM) on polyps and lumen-associated microbiota (LAM) analyses uncovered distinct bacterial signatures in the two groups. Importantly, we found an enrichment of the pathogenic species Finegoldia magna in MAM of OB patients, regardless of their polyp stage. We observed distinct mucosal-associated metabolome signatures, with OB patients showing increased pyroglutamic acid and reduced niacin levels, and performed microbiota-metabolome integrated analysis. These findings support a model where different risk factors may contribute to tumorigenesis in OB vs. NW patients, highlighting the potential impact of processed meat consumption and F. magna on CRC development among OB patients.

Whole-genome variants resource of 298 Saanen dairy goats

The Saanen breeds are often used as terminal sires for hybridization and play an important role in the global dairy food industry. However, there is still a lack of genomics information on the Saanen dairy goats. Whole-genome sequencing offers a promising approach to identify genetic markers associated with economic traits and discover new candidate genes. This can effectively utilize genetic resources to accelerate breeding processes and improve lactation performance in Saanen dairy goats. In this study, we present the genomes of 298 Saanen dairy goats. Through rigorous sequencing and quality control, we achieved an average sequencing depth of 14.6X, with 92.3% of high-quality (Q30 > 90%) data and an average mapping ratio of 99.9%, indicating reliable results. By comparing our data to a reference genome of Saanen dairy goats, we identified14.59 million single nucleotide polymorphisms (SNPs) and 1.34 million insertions-deletions (InDels). This dataset significantly contributes to enriching public databases in dairy goats and provides valuable resources for studying genetic diversity, improving breeds, and developing new varieties.

Identifying potential nutrient acquisition mechanisms for long-term survival: adaptive evolution of Halomonas isolated from subseafloor crustal fluids

In nature, microbes must often survive for long periods of time under conditions of nutrient and carbon limitation while also facing extremes in temperature, pressure, and competition with other microbes. One low-carbon, cold, and high pressure environment is the subseafloor crustal aquifer, where fluids circulate through old ocean crust. While microbial communities are known to be present in these fluids and contribute to biogeochemical cycling, the survival strategies of microbes in these communities is poorly constrained. In this study, multiple Halomonas strains were isolated from subseafloor crustal fluids of North Pond, a site located on the western flank of the Mid-Atlantic Ridge. These organisms are able to grow under laboratory conditions in minimal medium without the addition of carbon sources, as well as in rich nutrient conditions. We found that these Halomonas strains are highly related to each other in genomic content, but each strain has acquired unique mutations and/or undergone genomic rearrangements, suggesting that the strains were all derived from a single ancestral Halomonas progenitor. After serial passage of isolates from this Halomonas population under rich nutrient conditions in the laboratory, we identified mutants that can no longer scavenge scarce nutrients in minimal medium with no added carbon. Genomic analysis identified several genes that appear to be essential for survival under extremely low-nutrient condition, including several hypothetical proteins predicted to function as lipases, peptidases, or nutrient transporters. One of these genes was mutated in six out of the eight lineages studied, indicating that this hypothetical lipase protein is selected against during growth in rich medium, but may be required for growth under low-nutrient conditions. The application of an adaptive evolution platform selecting for survival and growth under one environmental condition that simultaneously selects against survival in different environments may prove to be a very useful tool for identifying genes and metabolic pathways in a wide variety of complex environments.

Genome sequences of Klebsiella pneumoniae bacteriophages SF_KL2 and SF_KL25

This report describes the genomes of Klebsiella pneumoniae phages SF_KL2 and SF_KL25, which infect the encapsulated multidrug-resistant K. pneumoniae known to cause nosocomial infections. SF_KL2 and SF_KL25 belong to the genus Webervirus (siphovirus morphotype) and have genomes of 48,737 and 49,170 bp, respectively. The phages were isolated from wastewater in northern Portugal.

Genomic and taxonomic characterization of the Comamonas sp. nov., a bacterium isolated from Brazilian Cerrado soil

A novel strain identified as Comamonas sp. was isolated from the soil of the Brazilian savanna-like Cerrado biome, a global hotspot for biodiversity. Phylogenetic analysis based on 16 S rRNA gene sequences showed that this strain is classified as Betaproteobacteria from the family Comamonadaceae. The digital DNA-DNA hybridization (dDDH) and Average Nucleotide Identity (ANI) results, of respectively 48.6% and < 93%, indicated that Comamonas sp. consists in a new species with Comamonas testosteroni as its closest strain. Comamonas sp. is a Gram-negative, rod-shaped, and non-spore-forming bacterium. Its colonies typically exhibit a round, convex, and irregular shape with a clear color and spotted edges. It is characterized as non-fermenting, aerobic, and motile, presenting both oxidase and catalase activities. The optimal growth parameters for this bacterial strain are 30 °C, a pH range of 5-8, and 0% NaCl. In addition, its fatty acid profile included palmitic acid (C16:0) at 26.94%, 13-Methyltetradecanoic Acid (iso-C15:0) at 10.94%, myristic acid (C14:0) at 8.94%, and a summed feature comprising 16:1 ω7c, 16:1 ω6c, or 16:1 at 15.8%. Genomic analysis of Comamonas sp. revealed a GC content of 62.1% across its 5.6 Mb genome. Phylogenomic and pangenome analyses, along with in silico phenotypic characterization indicate that this strain represents a novel species within the Comamonas genus, which we propose to name Comamonas brasiliensis nov.

Molecular evidence of Bartonella spp. in biting midges of the genus Culicoides Latreille (Diptera: Ceratopogonidae) from Brazil

Bartonella spp. are typical vector-borne pathogens, whose transmission has been primarily associated with a wide variety of hematophagous arthropods. These bacteria are responsible for several clinical syndromes in both humans and animals. The present study aimed to investigate the occurrence and molecular identity of Bartonella spp. in 345 specimens of Culicoides Latreille from the Brazilian Amazon. Out of 345 Culicoides specimens collected in the Amazon National Park, state of Pará, northern Brazil, 86.7 % (299/345) were positive for the endogenous cytochrome c oxidase subunit 1 gene. We detected a 24 % (72/299) prevalence rate for Bartonella spp. using a quantitative real-time PCR targeting the 16S-23S rRNA internal transcribed spacer (ITS) region. Culicoides foxi was statistically more associated with Bartonella positivity when compared to C. hylas and C. leopoldoi. Culicoides specimens collected at the ground level were more associated with positivity for Bartonella spp. when compared to those collected at the canopy. Further molecular characterization was performed using conventional PCR assays targeting seven molecular markers (nuoG, gltA, groEL, ftsZ, rpoB, pap31, and ribC). The BLASTn analysis revealed four gltA sequences with 99.72-100 % identity to Bartonella bovis previously detected in cattle from Brazil. One ribC sequence showed 100 % identity to Bartonella henselae previously detected in a cat from Germany. Six pap31 sequences showed 90-91 % identity to a Bartonella sp. sequence previously detected in a bat (Carollia perspicillata) from Brazil. This study represents the first molecular evidence of Bartonella spp. DNA in biting midges and contributes to understanding their role in the epidemiological cycles of these agents.

Potential of a newly isolated lytic bacteriophage to control Pseudomonas coronafaciens pv. garcae in coffee plants: Molecular characterization with in vitro and ex vivo experiments

Traditionally, control of coffee plant bacterial halo blight (BHB) caused by the phytopathogen Pseudomonas coronafaciens pv. garcae (Pcg) involves frequent spraying of coffee plantations with non-environmentally friendly and potentially bacterial resistance-promoting copper products or with kasugamycin hydrochloride. In this study we report a leap forward in the quest for a new ecofriendly approach, characterizing (both physicochemically and biologically) and testing both in vitro and ex vivo a new lytic phage for Pcg. An in-depth molecular (genomic and DNA structural features) characterization of the phage was also undertaken. Phage PcgS01F belongs to the class Caudoviricetes, Drexlerviridae family and genus Guelphvirus, and presents a siphovirus-like morphotype. Phage PcgS01F showed a latency period of 40 min and a burst size of 46 PFU/host cell, allowing to conclude that it replicates well in Pcg IBSBF-158. At Multiplicity Of Infection (MOI, or the ratio of phage to bacteria) 1000, the performance of phage PcgS01F was much better than at MOI 10, promoting increasing bacterial reductions until the end of the in vitro inactivation assays, stabilizing at a significant 82 % bacterial load reduction. Phage PcgS01F infected and killed Pcg cells ex vivo in coffee plant leaves artificially contaminated, with a maximum of Pcg inactivation of 7.66 log CFU/mL at MOI 1000 after 36 h of incubation. This study provides evidence that the isolated phage is a promising candidate against the causative agent of BHB in coffee plants.

Spoilage investigation of pasteurized apple juice with visual defects identifies a potentially novel Acetobacter species as the primary spoilage agent

Jellified materials were observed in spoiled pasteurized apple juice that contained dimethyl dicarbonate (DMDC). Microbiological analysis showed a high microbial load (4-5 log CFU/mL) in the sample. Acetobacter spp. was identified as the spoilage microorganism by 16S rRNA gene sequencing. Metataxonomic analysis showed Acetobacter represented 99 % of the bacterial community. Three Acetobacter isolates (LX5, LX9 and LX16) were selected for whole genome sequencing and characterized for their susceptibility to DMDC. Genome-based phylogeny supported the species-level classification of LX5 as A. fabarum. It also suggested LX9 and LX16 are the same microorganisms from a potentially novel species closely related to A. lovaniensis. The minimum inhibitory concentrations (MICs) of DMDC for Acetobacter isolates in sterile apple juice (pH ∼3) at 30 °C were 46 ppm and 329 ppm for A. fabarum LX5 and Acetobacter LX9/LX16, respectively. The minimum bactericidal concentrations (MBCs) were 250 and 500 ppm for A. fabarum LX5 and Acetobacter LX9/LX16, respectively. The inoculum concentration for the MIC assay was approximately 6 log10 CFU/mL, representing the "worst-case" scenario. When the contamination level was reduced to 500 CFU/mL per US federal regulation (21 CFR 172.133) and the apple juice was refrigerated, Acetobacter isolates did not grow and were completely inhibited by 238 ppm DMDC. Pangenome analysis identified gene clusters that potentially play a role in biofilm development, carbohydrate metabolism, and oxidative stress tolerance, but it also ruled out the involvement of Acetobacter in apple juice gel formation. The investigation concluded that post-pasteurization contamination, high microbial load and ambient storage were factors leading to this spoilage incident.

Barcode-free multiplex plasmid sequencing using Bayesian analysis and nanopore sequencing

Plasmid construction is central to life science research, and sequence verification is arguably its costliest step. Long-read sequencing has emerged as a competitor to Sanger sequencing, with the principal benefit that whole plasmids can be sequenced in a single run. Nevertheless, the current cost of nanopore sequencing is still prohibitive for routine sequencing during plasmid construction. We develop a computational approach termed Simple Algorithm for Very Efficient Multiplexing of Oxford Nanopore Experiments for You (SAVEMONEY) that guides researchers to mix multiple plasmids and subsequently computationally de-mixes the resultant sequences. SAVEMONEY defines optimal mixtures in a pre-survey step, and following sequencing, executes a post-analysis workflow involving sequence classification, alignment, and consensus determination. By using Bayesian analysis with prior probability of expected plasmid construction error rate, high-confidence sequences can be obtained for each plasmid in the mixture. Plasmids differing by as little as two bases can be mixed for submission as a single sample for nanopore sequencing, and routine multiplexing of even six plasmids per 180 reads can still maintain high accuracy of consensus sequencing. SAVEMONEY should further democratize whole-plasmid sequencing by nanopore and related technologies, driving down the effective cost of whole-plasmid sequencing to lower than that of a single Sanger sequencing run.

Diversity and phylogenetic position of the amphi-American lineages of the tapeworms of the genus Anthocephalum Linton, 1890 (Rhinebothriidea: Anthocephaliidae)

Among enduringly associated parasitic taxa, tapeworms (Platyhelminthes: Cestoda), particularly the family Anthocephaliidae Ruhnke, Caira & Cox, 2015, pose challenges to systematic history of the group. Within this family, the genus Anthocephalum Linton, 1890, remains insufficiently explored despite recent advancements. This study addresses the intricate taxonomy, phylogenetic relationships, diversity, and historical biogeography of tapeworms within the Anthocephaliidae, focusing on its type-genus Anthocephalum. To accomplish this objective, 15 specimens across various geographical regions including Alagoas and Pará in Brazil, Panama, and Senegal were selected for DNA extraction. For species of Anthocephalum, partial 18S and 28S rDNA sequences were amplified via PCR, purified, and sequenced using the ABI Big-Dye method. Three specimens of Alveobothrium grabatum Boudaya, Neifar & Euzet, 2018 were sequenced through Illumina technology. Phylogenetic analyses were conducted using IQTREE2 under two optimality criteria: Maximum Parsimony (MP) and Maximum Likelihood (ML). Biogeographic ancestral range estimations were performed using the R package BioGeoBEARS, incorporating multiple biogeographical models. Our phylogenetic analyses reaffirmed Anthocephaliidae's monophyly. However, both the relationships with or within Anthocephaliidae require further investigation. One example within the family is the positioning of Alveobothrium Boudaya, Neifar & Euzet, 2018, which challenged Anthocephalum's monophyly requiring taxonomic actions. Furthermore, when exploring new localities and/or new hosts for Anthocephalum, four independent lineages were identified, suggesting that Anthocephalum's diversity remains underestimated especially in unexplored regions and hosts. About the biogeographic ancestral range estimation, the analysis suggested a Central Indo-Pacific origin for early Anthocephalum lineages, with subsequent colonization events shaping the current diversity. The preliminary biogeographical framework presented here underscores the importance of refining phylogenetic hypotheses and enhancing taxonomic understanding. As taxonomic actions taken, the four new lineages were formally described and the genus Alveobothrium was synonymized with Anthocephalum, for which we proposed an amended diagnosis. This revision brings the total number of valid species of Anthocephalum to 30. Therefore, we suggest that future research initiatives should prioritize time-calibrated analyses, multiple genetic loci, and broader taxonomic representation for a detailed exploration of systematic history of anthocephaliid's.

Diversity of Cytauxzoon spp. (Piroplasmida: Theileriidae) in Wild Felids from Brazil and Argentina

Domestic and wild felids are frequently parasitized by apicomplexan protozoa in the genus Cytauxzoon. Expanding species diversity has recently been described within this genus, with potential implications for epidemiology and pathogenesis. In light of these findings, this study assessed the genetic diversity of Cytauxzoon spp. in wild felids (n = 66) from different eco-regions of Brazil and Argentina. Of the 66 blood samples analyzed, 53 (80.3%) were 18S rRNA gene PCR-positive for Cytauxzoon spp., including 43 jaguars (Panthera onca) and 10 ocelots (Leopardus pardalis). Panthera onca specimens (100%, 43/43) were most frequently infected, followed by Leopardus pardalis (76.9%; 10/13). Cytauxzoon spp. were not detected in Leopardus braccatus (n = 1) or Puma concolor (n = 9). Phylogenetic analyses of fragments of the 18S rRNA, cytB, and cox-1 gene sequences from jaguars were closely related to Cytauxzoon felis. In contrast, sequences from ocelots were more closely associated with Cytauxzoon brasiliensis. Distance and haplotype analysis further confirmed the circulation of at least two distinct genovariants of C. felis among jaguars, as evidenced by their close positioning and low genetic divergence (0-0.14% for 18S rRNA, 0.37-0.56% for cytB, and 0.08-0.74% for cox-1). Additionally, sequence data from ocelots suggested that multiple genovariants of C. brasiliensis are circulating among these cats in different Brazilian eco-regions. Our study provides evidence of two distinct Cytauxzoon organisms parasitizing free-ranging and captive jaguars and ocelots, respectively, in Brazil and Argentina.

Disease-associated Kv1.3 variants are energy compromised with impaired nascent chain folding

Human Kv1.3, encoded by KCNA3 , is expressed in neuronal and immune cells. Its impaired expression or function produces chronic inflammatory disease and autoimmune disorders, the severity of which correlates with Kv1.3 protein expression. The intersubunit recognition domain, T1, at the cytosolic N-terminus of Kv1.3, acquires secondary, tertiary, and quaternary structures during early biogenesis while the nascent protein is attached to the ribosome and/or the ER membrane. In this study, we ask whether native KCNA3 gene variants in T1 are associated with human disease and whether they manifest early-stage folding defects, energetic instabilities, and conformational distortion of subunits. We use three approaches: first, the unbiased "genome-first" approach to determine phenotype associations of specific KCNA3 rare variants. Second, we use biochemical assays to assess early-stage tertiary and quaternary folding and membrane association of these variants during early biogenesis. Third, we use all-atom molecular dynamics simulations of the T1 tetramer to assess structural macroscopic and energetic stability differences between wildtype (WT) Kv1.3 and a single-point variant, R114G. Measured folding probabilities and membrane associations are dramatically reduced in several of the native variants compared to WT. Simulations strikingly show that the R114G variant produces more energetically unstable and dynamic T1 domains, concomitant with tertiary unwinding and impaired formation of symmetrical tetramers. Our findings identify molecular mechanisms by which rare variants influence channel assembly, potentially contributing to diverse clinical phenotypes underlying human disease.

Population genetics analysis based on mitochondrial cytochrome c oxidase subunit I (CO1) gene sequences of Cottus koreanus in South Korea

BACKGROUND

The freshwater sculpin Cottus koreanus is endemic to the Korean Peninsula and has a fluvial life history. However, its population has been greatly reduced and it is now listed as an endangered class II species.

OBJECTIVE

To obtain important information for its conservation, we examine the genetic diversity, population structure, and demographic history of C. koreanus through mitochondrial cytochrome c oxidase subunit I (CO1) gene sequence analysis.

METHODS

We analyzed the CO1 gene sequences of 430 individuals of C. koreanus from 23 populations in South Korea.

RESULTS

In all, 32 haplotypes were defined by 124 variable nucleotide sites, of which 28 were unique haplotypes not shared with other regional populations. All sampled populations had high haplotype diversity (Hd = 0.941) and low nucleotide diversity (π = 0.0146). Median-joining network analysis identified two divergent clusters: cluster I that had unique haplotype patterns assigned to each population and cluster II that had a star-like pattern. Each was supported by pairwise FST values and hierarchical analysis of molecular variance. The results of the mismatch distribution, goodness-of-fit test, and extended Bayesian skyline plot analysis showed that cluster I has experienced a gradual population expansion since the last glacial maximum, while cluster II experienced a sudden one. The results of neutrality testing supported the results for cluster II but the signal was weak.

CONCLUSIONS

C. koreanus inhabits the upper reaches of rivers and has extremely low dispersal ability, resulting in unique genetic structure patterns among populations. Therefore, all populations should be managed and conserved separately.

Comparative transcriptome analysis and functional verification revealed that GhSAP6 negatively regulates salt tolerance in upland cotton

Owing to the scarcity of cultivable land in China, the agricultural sector is primarily focused on grain and oil crops. Simultaneously, the cultivation of cotton has gradually shifted towards regions characterized by elevated soil salinity levels. Additionally, the mechanism behind cotton's ability to tolerate salt remains elusive. In this study, we identified the Z9807 genotype as highly tolerant to salt stress, exhibiting superior leaf wilting resistance, antioxidant activity, catalase activity, K+/Na+ ratio, and growth compared to the salt-sensitive ZJ0102. Comparative transcriptome analysis revealed marked differences in salt stress responses between Z9807 and ZJ0102. This study identified a considerable number of differentially expressed genes associated with salt tolerance across multiple time points. By integration of QTL and GWAS mapping data, we successfully identified 621 candidate genes associated with salt tolerance. Weighted gene correlation network analysis exhibited three co-expression modules related to salt-tolerant Z9807 samples, ultimately identifying 15 core salt-tolerant candidate genes. We also conducted in-depth research on the salt tolerance of the stress-associated protein (SAP) GhSAP6 (GhSAP6_At and GhSAP6_Dt homologs). Results revealed that these candidate genes may inhibit salt tolerance through Virus-Induced Gene Silencing (VIGS) and transgenic overexpression assays conducted in Arabidopsis thaliana. Furthermore, we used yeast two-hybrid and luciferase assay experiments to confirm the ubiquitin degradation pathway between selected interacting proteins and verified the interaction with RAD23C. This study will provide new insights into the mechanisms related to salt tolerance in upland cotton.

LongReadSum: A fast and flexible quality control and signal summarization tool for long-read sequencing data

While several well-established quality control (QC) tools exist for short-read sequencing data, there is a general paucity of computational tools that efficiently deliver comprehensive metrics across a wide range of long-read sequencing data formats, such as Oxford Nanopore (ONT) POD5, ONT FAST5, ONT basecall summary, Pacific Biosciences (PacBio) unaligned BAM, and Illumina Complete Long Read (ICLR) FASTQ file formats. In addition to nucleotide sequence information, some file formats such as POD5 contain raw signal information used for base calling, while other file formats such as aligned BAM contain alignments to a linear reference genome or transcriptome and may also contain base modification information. There is currently no single available QC tool capable of summarizing each of these features. Furthermore, high-performance tools are required to efficiently process the growing data volumes from long-read sequencing platforms. To address these challenges, here we present LongReadSum, a high-performance tool for generating a summary QC report for major types of long-read sequencing data. We also demonstrate a few examples using LongReadSum to analyze cDNA sequencing, direct RNA sequencing, ONT reduced representation methylation sequencing (RRMS), and whole genome sequencing (WGS) data.

From Metagenomes to Functional Expression of Resistance: floR Gene Diversity in Bacteria from Salmon Farms

Background. The increase in antibiotic resistance in human-impacted environments, such as coastal waters with aquaculture activity, is related to the widespread use of antibiotics, even at sub-lethal concentrations. In Chile, the world's second largest producer of salmon, aquaculture is considered the main source of antibiotics in coastal waters. In this work, we aimed to characterize the genetic and phenotypic profiles of antibiotic resistance in bacterial communities from salmon farms. Methods. Bacterial metagenomes from an intensive aquaculture zone in southern Chile were sequenced, and the composition, abundance and sequence of antibiotic resistance genes (ARGs) were analyzed using assembled and raw read data. Total DNA from bacterial communities was used as a template to recover floR gene variants, which were tested by heterologous expression and functional characterization of phenicol resistance. Results. Prediction of ARGs in salmon farm metagenomes using more permissive parameters yielded significantly more results than the default Resistance Gene Identifier (RGI) software. ARGs grouped into drug classes showed similar abundance profiles to global ocean bacteria. The floR gene was the most abundant phenicol-resistance gene with the lowest gene counts, showing a conserved sequence although with variations from the reference floR. These differences were recovered by RGI prediction and, in greater depth, by mapping reads to the floR sequence using SNP base-calling. These variants were analyzed by heterologous expression, revealing the co-existence of high- and low-resistance sequences in the environmental bacteria. Conclusions. This study highlights the importance of combining metagenomic and phenotypic approaches to study the genetic variability in and evolution of antibiotic-resistant bacteria associated with salmon farms.

A novel genotype of Babesia microti-like group in Ixodes montoyanus ticks parasitizing the Andean bear (Tremarctos ornatus) in Ecuador

Babesia species (Piroplasmida) are hemoparasites that infect erythrocytes of mammals and birds and are mainly transmitted by hard ticks (Acari: Ixodidae). These hemoparasites are known to be the second most common parasites infecting mammals, after trypanosomes, and some species may cause malaria-like disease in humans. Diagnosis and understanding of Babesia diversity increasingly rely on genetic data obtained through molecular techniques. Among hard ticks, several Ixodes species are known vectors of Babesia microti-like species in the Northern Hemisphere. Recently, Ixodes and Amblyomma ticks have been recorded parasitizing the Andean bear (Tremarctos ornatus) in Ecuador. Previous reports have suggested babesiosis in a fatal case of this threatened bear species in that country. This study aimed to detect Piroplasmida DNA in hard ticks collected from Andean bears at two sites in Ecuador. This species plays a critical role as an ecological engineer and a seed disperses, contributing significantly to the maintenance and health of Andean ecosystems. Twelve ticks screened with conventional PCR and Piroplasmida DNA was amplified from one Ixodes montoyanus tick collected from a free-living female Andean bear at Llanganates National Park. Two Babesia sequences were characterized: one for the 18 S ribosomal rRNA gene and another for the cytochrome c oxidase 1 gene. Phylogenetic analyses for both loci placed these sequences within the B. microti-like clade. This study reports a novel B. microti-like genotype identified in an I. montoyanus parasitizing a female Andean bear, contributing to the knowledge of the diversity of this group in South America. Given their conservation status, future epidemiological surveillance of Babesia and other tick-borne infectious agents in Andean bears is needed.

Innovations in Transgene Integration Analysis: A Comprehensive Review of Enrichment and Sequencing Strategies in Biotechnology

Understanding the integration of transgene DNA (T-DNA) in transgenic crops, animals, and clinical applications is paramount for ensuring the stability and expression of inserted genes, which directly influence desired traits and therapeutic outcomes. Analyzing T-DNA integration patterns is essential for identifying potential unintended effects and evaluating the safety and environmental implications of genetically modified organisms (GMOs). This knowledge is crucial for regulatory compliance and fostering public trust in biotechnology by demonstrating transparency in genetic modifications. This review highlights recent advancements in T-DNA integration analysis, specifically focusing on targeted DNA enrichment and sequencing strategies. We examine key technologies, such as polymerase chain reaction (PCR)-based methods, hybridization capture, RNA/DNA-guided endonuclease-mediated enrichment, and high-throughput resequencing, emphasizing their contributions to enhancing precision and efficiency in transgene integration analysis. We discuss the principles, applications, and recent developments in these techniques, underscoring their critical role in advancing biotechnological products. Additionally, we address the existing challenges and future directions in the field, offering a comprehensive overview of how innovative DNA-targeted enrichment and sequencing strategies are reshaping biotechnology and genomics.

Phylogeographic and genetic insights into Sinonychia martensi: an endemic cave-dwelling harvestman in Beijing

Caves are one of the most exciting environments on earth, often considered an evolutionary laboratory due to the suite of convergent adaptive traits (troglomorphisms) of organisms inhabiting them. Sinonychia martensi Zhang & Derkarabetian, 2021, is the first and only Travunioidea species recorded in China and is endemic to Beijing, being known from multiple caves. However, nothing is known regarding its phylogeographic or evolutionary history. In this study, we assessed the species boundaries of S. martensi from nine caves using morphological and molecular methods to elucidate its phylogenetic position and genealogical relationships. We also investigated the genetic diversity, population genetic structure and demographic history of S. martensi to clarify the population-level relationships and make inferences about historical phylogeography. The results indicate that the species from different caves all belonged to S. martensi but represent different populations. These populations exhibit strong population structure and low genetic diversity. Cave populations may share a common ancestor and multiple independent invasions to different caves. The diversification within S. martensi was likely driven by climate change and subtropical evergreen broadleaf forests associated with the middle Miocene. This study highlights the need for further conservation efforts and exploration in Beijing caves.

Navigating triplet repeats sequencing: concepts, methodological challenges and perspective for Huntington's disease

The accurate characterization of triplet repeats, especially the overrepresented CAG repeats, is increasingly relevant for several reasons. First, germline expansion of CAG repeats above a gene-specific threshold causes multiple neurodegenerative disorders; for instance, Huntington's disease (HD) is triggered by >36 CAG repeats in the huntingtin (HTT) gene. Second, extreme expansions up to 800 CAG repeats have been found in specific cell types affected by the disease. Third, synonymous single nucleotide variants within the CAG repeat stretch influence the age of disease onset. Thus, new sequencing-based protocols that profile both the length and the exact nucleotide sequence of triplet repeats are crucial. Various strategies to enrich the target gene over the background, along with sequencing platforms and bioinformatic pipelines, are under development. This review discusses the concepts, challenges, and methodological opportunities for analyzing triplet repeats, using HD as a case study. Starting with traditional approaches, we will explore how sequencing-based methods have evolved to meet increasing scientific demands. We will also highlight experimental and bioinformatic challenges, aiming to provide a guide for accurate triplet repeat characterization for diagnostic and therapeutic purposes.

The role of sugar transporter BrSWEET11 in promoting plant early flowering and preliminary exploration of its molecular mechanism

KEY MESSAGE

BrSWEET11 accelerated Arabidopsis thaliana flowering, while silencing Brsweet11 in Brassica rapa delayed flowering relative to controls. BrSWEET11 is involved in sucrose transport after being induced by long-day conditions. SWEETs (Sugars Will Eventually Be Exported Transporters) are sugar outflow transporters that may participate in the regulation of plant flowering. In this study, the open reading frame of Brassica rapa ssp. pekinensis SWEET11 (BrSWEET11) was cloned and found to be 858 bp in length and encode 285 amino acids, which is typical of SWEET family proteins. The BrSWEET11 gene was strongly expressed in reproductive growth organs, particularly flowers, according to tissue expression analyses and GUS histochemical staining. BrSWEET11 promotes early flowering in Arabidopsis thaliana by 3-4 days, whereas Brsweet11 silencing in Brassica rapa delays flowering by 8-12 days relative to controls. BrSWEET11 promoted early flowering in A. thaliana, and compared with that in control plants, flowering was delayed in Brsweet11-silenced Brassica rapa. Transcriptome analysis of BrSWEET11-overexpressing A. thaliana and wild-type (WT) plants was performed and the results showed that eight key flowering genes jointly regulated flowering time, which was also validated in the Brsweet11-silenced plants. In addition, through photoperiod treatments and sugar content measurements, it was found that the expression of BrSWEET11 is induced by long-day conditions and is involved in sucrose transport. Further investigation using yeast library screening, yeast two-hybrid, and bimolecular fluorescence complementation assay techniques revealed that the BrSWEET11 protein interacts with the sugar transporter 4a (BrSUT4a) protein. Therefore, BrSWEET11 was induced by long-day conditions, and may promote early flowering in Brassica rapa through sucrose transport. This study provides a theoretical basis for elucidating the molecular mechanism through which SWEET genes are involved in flowering time regulation in Brassica rapa.

CopyMix: Mixture model based single-cell clustering and copy number profiling using variational inference

Investigating tumor heterogeneity using single-cell sequencing technologies is imperative to understand how tumors evolve since each cell subpopulation harbors a unique set of genomic features that yields a unique phenotype, which is bound to have clinical relevance. Clustering of cells based on copy number data obtained from single-cell DNA sequencing provides an opportunity to identify different tumor cell subpopulations. Accordingly, computational methods have emerged for single-cell copy number profiling and clustering; however, these two tasks have been handled sequentially by applying various ad-hoc pre- and post-processing steps; hence, a procedure vulnerable to introducing clustering artifacts. We avoid the clustering artifact issues in our method, CopyMix, a Variational Inference for a novel mixture model, by jointly inferring cell clusters and their underlying copy number profile. Our probabilistic graphical model is an improved version of the mixture of hidden Markov models, which is designed uniquely to infer single-cell copy number profiling and clustering. For the evaluation, we used likelihood-ratio test, CH index, Silhouette, V-measure, total variation scores. CopyMix performs well on both biological and simulated data. Our favorable results indicate a considerable potential to obtain clinical impact by using CopyMix in studies of cancer tumor heterogeneity.

Molecular detection and characterization of Anaplasmataceae agents, Bartonella spp. and hemoplasmas in armadillos and anteaters from Brazil

Armadillos and anteaters exhibit a wide range of interactions with various pathogens and ectoparasites, which, along with their physiological and ecological characteristics, contribute to their potential as hosts for a broad variety of pathogens with zoonotic potential. However, there has been limited research into the occurrence and diversity of vector-borne agents in this group of mammals. The present study aimed to investigate the occurrence and molecular identity of Ehrlichia spp., Anaplasma spp., Bartonella spp. and hemotropic mycoplasmas (hemoplasmas) in free-ranging armadillos and anteaters sampled in the southeast and central-west regions of Brazil. To this purpose, 167 biological samples (139 blood and 28 spleen) from Xenarthra mammals sampled in the states of São Paulo and Mato Grosso do Sul were analyzed: 48 from six-banded armadillos (Euphractus sexcinctus), 29 from giant armadillos (Priodontes maximus), 4 from nine-banded armadillos (Dasypus novemcinctus), 1 from naked-tailed armadillo (Cabassous unicinctus), 79 from giant anteaters (Myrmecophaga tridactyla) and 6 from southern tamanduas (Tamandua tetradactyla). Screening PCR assays were performed for Ehrlichia spp. based on the dsb gene, nested PCR for Anaplasma spp. and PCR for hemotropic mycoplasmas based on the 16S rRNA gene, and qPCR for Bartonella spp. based on the 16-23S rRNA intergenic region (ITS). The positive samples were additionally subjected to PCR assays targeting different molecular markers for molecular characterization. As a result, 1/48 (0.59%) blood sample from E. sexcintus was positive for Anaplasma spp., and 1/79 (0.59%) blood sample from M. tridactyla was positive for Ehrlichia spp. The 16S rRNA sequence of Anaplasma sp. detected in E. sexcintus clustered within the same clade as 'Candidatus Anaplasma brasiliensis', previously detected in T. tetradactyla. The dsb sequence of Ehrlichia sp. detected in M. tridactyla clustered within the same clade as Ehrlichia minasensis. In the PCR tests for hemoplasmas, 31/46 (64.5%) E. sexcinctus, 9/29 (65.5%) P. maximus, 2/4 (50%) D. novemcinctus, 33/79 (41.7%) M. tridactyla, and 2/6 (33.3%) T. tetradactyla tested positive. The 16S rRNA and 23S rRNA sequences of hemoplasmas found in E. sexcinctus clustered within the same clade as 'Candidatus Mycoplasma haematomaximus', which was previously detected in P. maximus in Brazil. High positivity rates were also observed for Bartonella spp., with 23/48 (47.9%) E. sexcinctus, 1/4 (25%) D. novemcinctus, 9/29 (31%) P. maximus, 21/79 (26.5%) M. tridactyla, and 3/6 (50%) T. tetradactyla showing positive results. The ftsZ sequences of Bartonella sp. detected in E. sexcinctus clustered with 'Candidatus Bartonella washoensis subsp. brasiliensis', previously identified in six-banded armadillos in Brazil. These findings reinforce the presence of 'Candidatus Anaplasma brasiliensis' and 'Candidatus Bartonella washoensis subsp. brasiliensis' in armadillos, and Ehrlichia minasensis in anteaters. This is the first report of 'Candidatus Mycoplasma haematomaximus', a hemoplasma previously described in giant armadillos, in six-banded armadillos. The zoonotic potential and real significance of infection by these agents in xenarthrans' health and conservation efforts are yet to be investigated.

A RETREG1 variant is associated with hereditary sensory and autonomic neuropathy with acral self-mutilation in purebred German Spitz

Hereditary sensory and autonomic neuropathies (HSAN) represent a group of genetic diseases affecting the peripheral nervous system. In humans, at least 16 loci have been associated with the disorder but do not explain the disease origin of all patients. In dogs, similar conditions have been documented for decades in various breeds with a severe impact on life quality and are often referred to as acral mutilation syndrome (AMS). Causal variants in three genes have been identified to date, suggesting larger genetic heterogeneity in the dog population. Our aim was to explain the genetic etiology of an early-onset HSAN/AMS in a purebred German Spitz. The affected dog showed progressive loss of pain sensation in the distal extremities, which led to intense licking, biting, and self-mutilation of digits and paw pads. Whole-genome sequencing identified a single candidate causal variant on chromosome 4 in the RETREG1 gene (c.656C>T, p.Pro219Leu). This missense variant was previously recognized as deleterious in a mixed breed dog family with similar clinical signs. Haplotype analyses and targeted genotyping revealed a likely German Spitz ancestry of these mixed breed dogs. Further screening of an extensive cohort of ~900 000 dogs of various breeds hinted at the variant allele origin in the German Spitz breed. Disruption of RETREG1 inhibits endoplasmic reticulum turnover and leads to neuron degeneration. Our findings provide evidence that this variant underlies the recessive form of HSAN/AMS in the German Spitz and support the use of whole-genome sequencing-based veterinary precision medicine for early diagnosis and prevention via a genetic test.

Genetic diversity of Theileria spp. in deer (Artiodactyla: Cervidae) from Brazil

Babesia spp. and Theileria spp. are tick-borne apicomplexan protozoa that can cause disease in animals and humans. Deer are considered reservoirs for a wide variety of Piroplasmida species, including some potentially zoonotic. This study aimed to investigate the occurrence and genetic diversity of piroplasmids in wild deer sampled in four Brazilian states (São Paulo, Mato Grosso do Sul, Paraná and Goiás). For this purpose, extracted DNA samples from 181 deer buffy coat samples (138 Blastocerus dichotomus, 26 Subulo gouazoubira, 4 Mazama jucunda, 3 Mazama rufa and 10 Ozotocerus bezoarticus) were subjected to a nested PCR (nPCR) assay based on the 18S rRNA gene in order to perform a screening for piroplasmids and characterized based on the near-complete 18S rRNA, hsp70 and cox-3 genes. As a result, 75.14% (136/181) samples were positive for piroplasmids. Of these, 108 (79.41%), 101 (74.26%) and 67 (49.26%) were positive to near complete 18S rRNA, hsp70 and cox-3 genes, respectively. Phylogenetic analyses based on three molecular markers showed similar topology to each other. All sequences obtained in the present study were positioned into the Theileria sensu stricto clade, forming a distinct clade, albeit close to T. cervi. Most sequences grouped together into a large clade divided into subclades, which were often related to deer genus/species, showing that Theileria lineages seemed to show specificity according to deer genus/species. Two 18S rRNA sequences (one obtained from S. gouazoubira and another from M. jucunda) were positioned into a different clade, apart from other sequences detected in this study, indicating that different species of Theileria occur in deer from Brazil. Two subclusters were observed in the phylogenetic analysis based on the hsp70 gene: the first containing only sequences detected in marsh deer and the second grouping sequences detected in brocket deer (Mazama spp. and S. gouazoubira). The latter was also divided into smaller clades that grouped Theileria genotypes according to deer species (M. jucunda, M. rufa and S. gouazoubira). This study provides the first molecular evidence of Theileria infection in M. jucunda, as well as co-infection by distinct Theileria (sub)species/genotypes in the same deer was evidenced. Finally, this study expanded the knowledge on the diversity of Theileria spp. infecting deer from South America.

Transcriptome and genome-wide analysis of the potential role of SKP1 gene family in the development of floral organs of two related species of Allium fistulosum

Allium fistulosum is an important plant germplasm resource, rich in nutrients and possessing unique medicinal value. However, due to its small floral organs, low seed setting rate of a single flower, high cost of artificial emasculation, and artificial pollination, the use of male sterile lines to prepare Allium hybrids has become a common choice. In this study, A. fistulosum var. viviparum Makino and A. galanthum were used as materials to study the regulation mechanism of anther development, aiming to provide a reference for male sterility. Through transcriptome differential gene screening and genome-wide bioinformatics analysis, 34 SKP1 (S-phase kinase-associated protein 1) genes (AfSKP1-1 to AfSKP1-34) were identified in the whole genome of A. fistulosum. The AfSKP1 genes are unevenly distributed on eight chromosomes. Furthermore, two pairs of collinear relationships are evident among family members, and fragment replication events between AfSKP1 genes have been identified. The phylogenetic tree analysis demonstrated that the AfSKP1, AtSKP1, OsSKP1, and SlSKP1 genes were clustered into six groups, exhibiting a gene structure analogous to that observed in members of an evolutionary classification. A combination of gene structure and phylogenetic analysis revealed the presence of cis-acting elements associated with growth, hormone regulation, and stress response within the AfSKP1 genes. Furthermore, expression analysis demonstrated that the AfSKP1 genes exhibited differential expression patterns across various tissues of A. fistulosum. The tissue-specific expression of the AfSKP1 gene was verified by Real-Time PCR. A comparison of the two materials revealed significant differences in the expression of the AfSKP1-8 gene in floral buds, the AfSKP1-11 gene in inflorescence meristems, and the AfSKP1-14 gene in inflorescence meristems, scapes, and floral buds. The results indicated that the three genes may be involved in anther development, thereby providing a theoretical basis for further study of floral organ development and pollen development in AfSKP1 family members.

The quality and detection limits of mitochondrial heteroplasmy by long read nanopore sequencing

This study evaluates long-read and short-read sequencing for mitochondrial DNA (mtDNA) heteroplasmy detection. 592,315 bootstrapped datasets generated from two single-nucleotide mismatched ultra-deep sequenced mtDNA samples were used to assess basecalling error and accuracy, limit of heteroplasmy detection, and heteroplasmy detection across various coverage depths. Results showed high Phred scores of data with GC-rich sequence bias for long reads. Limit of detection of 12% heteroplasmy was identified, showing strong correlation (R2 ≥ 0.955) with expected heteroplasmy but underreporting tendency of high-level variants. Nanopore sequencing shows potential for direct applicability in mitochondrial diseases diagnostics, but stringent validation processes to ensure diagnostic result quality are required.

Transcriptomic analysis of the 12 major human breast cell types reveals mechanisms of cell and tissue function

A fundamental question in biology, central to our understanding of cancer and other pathologies, is determining how different cell types coordinate to form and maintain tissues. Recognizing the distinct features and capabilities of the cells that compose these tissues is critical. Unfortunately, the complexity of tissues often hinders our ability to distinguish between neighboring cell types and, in turn, scrutinize their transcriptomes and generate reliable and tractable cell models for studying their inherently different biologies. We have recently introduced a novel method that permits the identification and purification of the 12 cell types that compose the human breast-nearly all of which could be reliably propagated in the laboratory. Here, we explore the nature of these cell types. We sequence mRNAs from each purified population and investigate transcriptional patterns that reveal their distinguishing features. We describe the differentially expressed genes and enriched biological pathways that capture the essence of each cell type, and we highlight transcripts that display intriguing expression patterns. These data, analytic tools, and transcriptional analyses form a rich resource whose exploration provides remarkable insights into the inner workings of the cell types composing the breast, thus furthering our understanding of the rules governing normal cell and tissue function.

Serological and molecular diagnosis of Trypanosoma vivax on buffalos (Bubalus bubalis) and their ectoparasites in the lowlands of Maranhão, Brazil

The aim of this study was to detect trypomastigote forms of Trypanosoma vivax, in blood smears, DNA of T. vivax and anti-T. vivax antibodies in samples from buffalos reared in the lowlands of Maranhão, Brazil. Blood samples were collected from 116 buffalos and 25 ectoparasite specimens. Blood smears were produced to diagnose forms compatible with Trypanosoma spp.; the indirect enzyme-linked immunosorbent assay (iELISA) and lateral-flow immunochromatography (Imunotest®) serological tests were used; and the polymerase chain reaction (PCR) was used to make molecular diagnoses. No forms compatible with Trypanosoma spp. were observed in blood smears. Among the 116 serum samples analyzed, 79.31% and 76.72% were positive in the ELISA and rapid tests, respectively. One sample was positive in the molecular test. Twenty-five lice of the species Haematopinus tuberculatus were collected. When subjected to PCR for detection of DNA of T. vivax, all of them were negative. The louse specimens were negative for T. vivax. There were no statistically significant differences (p < 0.05) in the presence of T. vivax in this region, in relation to the animals' age and sex. It can be concluded that these protozoa are circulating in the buffalo herd of the lowlands of Maranhão displaying crypitc parasitemias.

Global transcription and metabolic profiles of five tissues in pepper fruits

Studying the regulatory mechanisms in different tissues of pepper is crucial for understanding organ formation, growth, and development. However, relevant studies are far from sufficient. In the current study, the stipe, calyx, pericarp, placenta, and seed of ripe pepper were sampled, and metabolites were determined by the untargeted metabolomics method. Transcriptome sequencing was performed by Illumina NovaSeq 6000, and then a high-throughput data set was built. The results showed that a total of 4879 annotated metabolites were detected in 15 samples of the five tissues under positive and negative ion mode. A total of 110.66 Gb of clean data was obtained by transcriptome sequencing, the clean data of each sample reached 6.21 Gb, and a total of 35 336 annotated expression genes were obtained. Furthermore, validate the accuracy of the data by combining principal component analysis and other methods. In summary, this study provides valuable information for the genetic improvement and breeding of peppers, and it holds potential application value, particularly in enhancing the quality and nutritional value of pepper fruits.

Assessment of the Impact of Preanalytical DNA Integrity on the Genome Data Quality

Many molecular approaches have been employed for the quality control (QC) of biobanked DNA samples. Since 2003, the National Biobank of Korea (NBK) has provided various studies with over half a million quality-controlled genomic DNA samples using conventional agarose gel electrophoresis and spectrophotometry. We assessed the postanalytical genomic data quality of DNA samples (n = 41) with a different range of the DNA quality index such as genomic quality number (GQN) for developing an evidence-based best practice for DNA quality criteria. We examined the quality indices of three different platforms, including single nucleotide polymorphism arrays, methylation arrays, and next-generation sequencing, using the same DNA samples (n = 41) of different quality, ranging from 4.0 to 10.0 values of the GQN. Our data analysis revealed that higher GQN value and/or double-stranded DNA concentration resulted in higher quality genomic data. In addition, all the analyzed DNA samples successfully generated good-quality genomic data. This study provides a guide for the QC of biobanked DNA samples for genomic analysis platforms.

Dissecting the genetic architecture of sunflower disc diameter using genome-wide association study

Sunflower (Helianthus annuus L.) plays an essential role in meeting the demand for edible oil worldwide. The yield of sunflower seeds encompasses several component traits, including the disc diameter. Over three consecutive years, 2019, 2020, and 2022, we assessed phenotypic variation in disc diameter across a diverse set of sunflower accessions (N = 342) in replicated field trials. Upon aggregating the phenotypic data from multiple years, we estimated the broad sense heritability (H 2) of the disc diameter trait to be 0.88. A subset of N = 274 accessions was genotyped by using the tunable genotyping-by-sequencing (tGBS) method, resulting in 226,779 high-quality SNPs. Using these SNPs and the disc diameter phenotype, we conducted a genome-wide association study (GWAS) employing two statistical approaches: the mixed linear model (MLM) and the fixed and random model circulating probability unification (farmCPU). The MLM and farmCPU GWAS approaches identified 106 and 8 significant SNPs located close to 53 and 21 genes, respectively. The MLM analysis identified two significant peaks: a prominent signal on chromosome 10 and a relatively weaker signal on chromosome 16, both of which were also detected by farmCPU. The genetic loci associated with disc diameter, as well as the related candidate genes, present promising avenues for further functional validation and serve as a basis for sunflower oil yield improvement.

Host genetics and microbiota data analysis in colorectal cancer research

Colorectal cancer (CRC) is a heterogeneous disease with a complex aetiology influenced by a myriad of genetic and environmental factors. Despite advances in CRC research, it is a major burden of disease, with the second highest incidence and third leading cause of cancer deaths worldwide. To individualise diagnosis, prognosis, and treatment of CRC, developing new strategies combining precision medicine and bioinformatic procedures is promising. Precision medicine is based on omics technologies and aims to individualise the management of CRC based on patient host genetic characteristics and microbiota. Bioinformatics is central to the application of personalised medicine because it enables the analysis of large datasets generated by these technologies. At the level of host genetics, bioinformatics allows the identification of mutations, genes, molecular pathways, biomarkers and drugs relevant to colorectal carcinogenesis. At the microbiota level, bioinformatics is fundamental to analysing microbial communities' composition and functionality and developing biomarkers and personalised microbiota-based therapies. This paper explores the host and microbiota genetic data analysis in CRC research.

Challenges in molecular diagnosis of multiple endocrine neoplasia

Multiple endocrine neoplasia (MEN) is a group of rare genetic diseases characterized by the occurrence of multiple tumors of the endocrine system in the same patient. The first MEN described was MEN1, followed by MEN2A, and MEN2B. The identification of the genes responsible for these syndromes led to the introduction of family genetic screening programs. More than twenty years later, not all cases of MENs have been resolved from a genetic point of view, and new clinicogenetic entities have been described. In this review, we will discuss the strategies and difficulties of genetic screening for classic and newly described MENs in a clinical setting, from limitations in sequencing, to problems in classifying variants, to the identification of new candidate genes. In the era of genomic medicine, characterization of new candidate genes and their specific tumor risk is essential for inclusion of patients in personalized medicine programs as well as to permit accurate genetic counseling to be proposed for families.

Enhancing schizophrenia phenotype prediction from genotype data through knowledge-driven deep neural network models

This article explores deep learning model design, drawing inspiration from the omnigenic model and genetic heterogeneity concepts, to improve schizophrenia prediction using genotype data. It introduces an innovative three-step approach leveraging neural networks' capabilities to efficiently handle genetic interactions. A locally connected network initially routes input data from variants to their corresponding genes. The second step employs an Encoder-Decoder to capture relationships among identified genes. The final model integrates knowledge from the first two and incorporates a parallel component to consider the effects of additional genes. This expansion enhances prediction scores by considering a larger number of genes. Trained models achieved an average AUC of 0.83, surpassing other genotype-trained models and matching gene expression dataset-based approaches. Additionally, tests on held-out sets reported an average sensitivity of 0.72 and an accuracy of 0.76, aligning with schizophrenia heritability predictions. Moreover, the study addresses genetic heterogeneity challenges by considering diverse population subsets.

3,3-Dimethyl-1-Butanol and its Metabolite 3,3-Dimethylbutyrate Ameliorate Collagen-induced Arthritis Independent of Choline Trimethylamine Lyase Activity

Conflicting data exist in rheumatoid arthritis and the collagen-induced arthritis (CIA) murine model of autoimmune arthritis regarding the role of bacterial carnitine and choline metabolism into the inflammatory product trimethylamine (TMA), which is oxidized in the liver to trimethylamine-N-oxide (TMAO). Using two published inhibitors of bacterial TMA lyase, 3,3-dimethyl-1-butanol (DMB) and fluoromethylcholine (FMC), we tested if TMA/TMAO were relevant to inflammation in the development of CIA. Surprisingly, DMB-treated mice demonstrated > 50% reduction in arthritis severity compared to FMC and vehicle-treated mice, but amelioration of disease was independent of TMA/TMAO production. Given the apparent contradiction that DMB did not inhibit TMA, we then investigated the mechanism of protection by DMB. After verifying that DMB acted independently of the intestinal microbiome, we traced the metabolism of DMB within the host and identified a novel host-derived metabolite of DMB, 3,3-dimethyl-1-butyric acid (DMBut). In vivo studies of mice treated with DMB or DMBut demonstrated efficacy of both molecules in significantly reducing disease and proinflammatory cytokines in CIA, while in vitro studies suggest these molecules may act by modulating secretion of proinflammatory cytokines from macrophages. Altogether, our study suggests that DMB and/or its metabolites are protective in CIA through direct immunomodulatory effects rather than inhibition of bacterial TMA lyases.

Dissecting the Genetic Architecture of Morphological Traits in Sunflower (Helianthus annuus L.)

The sunflower (Helianthus annuus L.) is one of the most essential oil crops in the world. Several component traits, including flowering time, plant height, stem diameter, seed weight, and kernel weight, determine sunflower seed and oil yield. Although the genetic mechanisms governing the variation of these yield-related traits have been studied using various approaches, genome-wide association studies (GWAS) have not been widely applied to sunflowers. In this study, a set of 342 sunflower accessions was evaluated in 2019 and 2020 using an incomplete randomized block design, and GWAS was conducted utilizing two complementary approaches: the mixed linear model (MLM) and the fixed and random model circulating probability unification (farmCPU) model by fitting 226,779 high-quality SNPs. As a result, GWAS identified a number of trait-associated SNPs. Those SNPs were located close to several genes that may serve as a basis for further molecular characterization and provide promising targets for sunflower yield improvement.

Genomic and molecular characterization of a cyprinid herpesvirus 2 YC-01 strain isolated from gibel carp

Cyprinid herpesvirus 2 (CyHV-2) is the pathogen of herpesviral hematopoietic necrosis (HVHN), causing the severe economic losses in farmed gibel carp (Carassius gibelio). Further exploration of the genome structure and potential molecular pathogenesis of CyHV-2 through complete genome sequencing, comparative genomics, and molecular characterization is required. Herein, the genome of a CyHV-2 YC-01 strain isolated from diseased gibel carp collected in Yancheng, Jiangsu Province, China was sequenced, then we analyzed the genomic structure, genetic properties, and molecular characterization. First, the complete YC-01 genome comprises 275,367 bp without terminal repeat (TR) regions, with 151 potential open reading frames (ORFs). Second, compared with other representative published strains of the genus Cyvirus, several evident variations are found in YC-01, particularly the orientation and position of ORF25 and ORF25B. ORF107 and ORF156 are considered as potential molecular genetic markers for YC-01. ORF55 (encoding thymidine kinase) might be used to distinguish YC-01 and ST-J1 from other CyHV-2 isolates. Third, phylogenetically, YC-01 clusters with the members of the genus Cyvirus (together with the other six CyHV-2 isolates). Fourth, 43 putative proteins are predicted to be functional and are mainly divided into five categories. Several conserved motifs are found in nucleotide, amino acid, and promoter sequences including cis-acting elements identification of YC-01. Finally, the potential virulence factors and linear B cell epitopes of CyHV-2 are predicted to supply possibilities for designing novel vaccines rationally. Our results provide insights for further understanding genomic structure, genetic evolution, and potential molecular mechanisms of CyHV-2.

Chasing Sequencing Perfection: Marching Toward Higher Accuracy and Lower Costs

Next-generation sequencing (NGS), represented by Illumina platforms, has been an essential cornerstone of basic and applied research. However, the sequencing error rate of 1 per 1000 bp (10-3) represents a serious hurdle for research areas focusing on rare mutations, such as somatic mosaicism or microbe heterogeneity. By examining the high-fidelity sequencing methods developed in the past decade, we summarized three major factors underlying errors and the corresponding 12 strategies mitigating these errors. We then proposed a novel framework to classify 11 preexisting representative methods according to the corresponding combinatory strategies and identified three trends that emerged during methodological developments. We further extended this analysis to eight long-read sequencing methods, emphasizing error reduction strategies. Finally, we suggest two promising future directions that could achieve comparable or even higher accuracy with lower costs in both NGS and long-read sequencing.

Phylogenetic inferences based on distinct molecular markers reveals a novel Babesia (Babesia pantanalensis nov. sp.) and a Hepatozoon americanum-related genotype in crab-eating foxes (Cerdocyon thous)

Piroplasmids and Hepatozoon spp. Are apicomplexan protozoa that may cause disease in several canid species. The present study aimed to expand the knowledge on the diversity of piroplasmids and Hepatozoon in crab-eating foxes (Cerdocyon thous; n = 12) sampled in the Pantanal of Mato Grosso do Sul State, central-western Brazil. PCR assays based on the 18S rRNA were used as screening. Three (25%) and 11 (91.7%) were positive for piroplasmids and Hepatozoon spp., respectively. Co-infection was found in three C. thous. Phylogenetic analyses based on the near-complete 18S rRNA, cox-1 and hsp70 genes evidenced the occurrence of a novel of Babesia spp. (namely Babesia pantanalensis nov. sp.) closely related to Rangelia vitalii and Babesia sp. 'Coco'. This finding was supported by the genetic divergence analysis which showed (i) high divergence, ranging from 4.17 to 5.62% for 18 S rRNA, 6.16% for hps70 and 4.91-9.25% for cox-1 and (ii) the genotype network (which displayed sequences separated from the previously described Piroplasmida species by median vectors and several mutational events). Also, phylogenetic analysis based on the 18S rRNA gene of Hepatozoon spp. positioned the sequences obtained herein in a clade phylogenetically related to Hepatozoon sp. 'Curupira 2', Hepatozoon sp. detected in domestic and wild canids from Uruguay and Hepatozoon americanum. The present study described Babesia pantanalensis nov sp. and Hepatozoon closely related to H. americanum in crab-eating foxes from Brazil. Moreover, the coinfection by piroplasmids and Hepatozoon sp. for the first time in crab-eating foxes strongly suggesting that this wild canid species potentially acts as a bio-accumulate of hemoprotozoan in wild environment.

Evidence for human-caused founder effect in populations of Solanum jamesii at archaeological sites: II. Genetic sequencing establishes ancient transport across the Southwest USA

PREMISE

The domestication of wild plant species can begin with gathering and transport of propagules by Indigenous peoples. The effect on genomic composition, especially in clonal, self-incompatible perennials would be instantaneous and drastic with respect to new, anthropogenic populations subsequently established. Reductions in genetic diversity and mating capability would be symptomatic and the presence of unique alleles and genetic sequences would reveal the origins and ancestry of populations associated with archaeological sites. The current distribution of the Four Corners potato, Solanum jamesii Torr. in the Southwestern USA, may thus reflect the early stages of a domestication process that began with tuber transport.

METHODS

Herein genetic sequencing (GBS) data are used to further examine the hypothesis of domestication in this culturally significant species by sampling 25 archaeological and non-archaeological populations.

RESULTS

Archaeological populations from Utah, Colorado and northern Arizona have lower levels of polymorphic loci, unique alleles, and heterozygosity than non-archaeological populations from the Mogollon region of central Arizona and New Mexico. Principle components analysis, Fst values, and structure analysis revealed that genetic relationships among archaeological populations did not correspond to geographic proximity. Populations in Escalante, Utah were related to those on the Mogollon Rim (400 km south) and had multiple origins and significant disjunctions with those populations in Bears Ears, Chaco Canyon, and Mesa Verde sites.

CONCLUSIONS

Movement of tubers from the Mogollon region may have occurred many times and in multiple directions during the past, resulting in the complex genetic patterns seen in populations from across the Four Corners region.

Transcriptome sequencing of the endangered land snail Karaftohelix adamsi from the Island Ulleung: De novo assembly, annotation, valuation of fitness genes and SSR markers

BACKGROUND

The Bradybaenidae snail Karaftohelix adamsi is endemic to Korea, with the species tracked from Island Ulleung in North Gyeongsang Province of South Korea. K. adamsi has been classified under the Endangered Wildlife Class II species of Korea and poses a severe risk of extinction following habitat disturbances. With no available information at the DNA (genome) or mRNA (transcriptome) level for the species, conservation by utilizing informed molecular resources seems difficult.

OBJECTIVE

In this study, we used the Illumina short-read sequencing and Trinity de novo assembly to draft the reference transcriptome of K. adamsi.

RESULTS

After assembly, 13,753 unigenes were obtained of which 10,511 were annotated to public databases (a maximum of 10,165 unigenes found homologs in PANM DB). A total of 6,351, 3,535, 358, and 3,407 unigenes were ascribed to the functional categories under KOG, GO, KEGG, and IPS, respectively. The transcripts such as the HSP 70, aquaporin, TLR, and MAPK, among others, were screened as putative functional resources for adaptation. DNA transposons were found to be thickly populated in comparison to retrotransposons in the assembled unigenes. Further, 2,164 SSRs were screened with the promiscuous presence of dinucleotide repeats such as AC/GT and AG/CT.

CONCLUSION

The transcriptome-guided discovery of molecular resources in K. adamsi will not only serve as a basis for functional genomics studies but also provide sustainable tools to be utilized for the protection of the species in the wild. Moreover, the development of polymorphic SSRs is valuable for the identification of species from newer habitats and cross-species genotyping.

De-novo assembly of four rail (Aves: Rallidae) genomes: A resource for comparative genomics

Rails are a phenotypically diverse family of birds that includes 130 species and displays a wide distribution around the world. Here we present annotated genome assemblies for four rails from Aotearoa New Zealand: two native volant species, pūkeko Porphyrio melanotus and mioweka Gallirallus philippensis, and two endemic flightless species takahē Porphyrio hochstetteri and weka Gallirallus australis. Using the sequence read data, heterozygosity was found to be lowest in the endemic flightless species and this probably reflects their relatively small populations. The quality checks and comparison with other rallid genomes showed that the new assemblies were of good quality. This study significantly increases the number of available rallid genomes and will enable future genomic studies on the evolution of this family.

Whole genome sequencing of HER2-positive metastatic extramammary Paget's disease: a case report

BACKGROUND

Extramammary Paget's disease (EMPD) is a rare cancer that occurs within the epithelium of the skin, arising predominantly in areas with high apocrine gland concentration such as the vulva, scrotum, penis and perianal regions. Here, we aim to integrate clinicopathological data with genomic analysis of aggressive, rapidly-progressing de novo metastatic EMPD responding to HER2-directed treatment in combination with other agents, to attain a more comprehensive understanding of the disease landscape.

METHODS

Immunohistochemical staining on the scrotal wall tumor and bone marrow metastasis demonstrated HER2 overexpression. Whole genome sequencing of the tumor and matched blood was performed.

RESULTS

Notable copy number gains (log2FC > 0.9) on chromosomes 7 and 8 were detected (n = 81), with 92.6% of these unique genes specifically located on chromosome 8. Prominent cancer-associated genes include ZNF703, HOOK3, DDHD2, LSM1, NSD3, ADAM9, BRF2, KAT6A and FGFR1. Interestingly, ERBB2 gene did not exhibit high copy number gain (log2FC = 0.4) although 90% of tumor cells stained HER2-positive. Enrichment in pathways associated with transforming growth factor-beta (TGFβ) (FDR = 0.0376, Enrichment Ratio = 8.12) and fibroblast growth factor receptor (FGFR1) signaling (FDR = 0.0082, Enrichment Ratio = 2.3) was detected. Amplicon structure analysis revealed that this was a simple-linear amplification event.

CONCLUSION

Whole genome sequencing revealed the underlying copy number variation landscape in HER2-positive metastatic EMPD. The presence of alternative signalling pathways and genetic variants suggests potential interactions with HER2 signalling, which possibly contributed to the HER2 overexpression and observed response to HER2-directed therapy combined with other agents in a comprehensive treatment regimen.