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At present, many infectious pathogens, especially emerging/re-emerging pathogens, exist in the blood of voluntary blood donors and may be transmitted through blood transfusions. However, most of Chinese blood centers only routinely screen for HBV, HCV, HIV, and syphilis. We employed metagenomic next-generation sequencing (mNGS) to investigate the microbiome in healthy voluntary blood donors to help assess blood safety in China by identifying infectious pathogens presented in donations that could lead to transfusion-acquired infections. We collected 10,720 plasma samples from voluntary blood donors from seven blood centers in different cities during 2012–2018 in China. A total of 562 GB of clean data was obtained. By analyzing the sequencing data, it was found that the most commonly identified bacteria found in the healthy blood were Serratia spp. (5.0176%), Pseudomonas spp. (0.6637%), and Burkholderia spp. (0.5544%). The principal eukaryote were Leishmania spp (1.3723%), Toxoplasma gondii (0.6352%), and Candida dubliniensis (0.1848%). Among viruses, Human Parvovirus B19 (B19V) accounts for the highest proportion (0.1490%), followed by Torque teno midi virus (0.0032%) and Torque teno virus (0.0015%). Since that B19V is a non-negligible threat to blood safety, we evaluated the positive samples for B19V tested by mNGS using quantitative polymerase chain reaction, Sanger sequencing, and phylogenetic analysis to achieve a better understanding of B19V in Chinese blood donors. Subsequently, 9 (0.07%) donations were positive for B19V DNA. The quantitative DNA levels ranged from 5.58 × 102 to 7.24 × 104 IU/ml. The phylogenic analyses showed that prevalent genotypes belonged to the B19-1A subtype, which disclosed previously unknown regional variability in the B19V positivity rate. The investigation revealed that many microbes dwell in the blood of healthy donors, including some pathogens that may be dormant in the blood and only cause disease under specific conditions. Thus, investigating the range and nature of potential pathogens in the qualified donations provided a framework for targeted interventions to help prevent emerging and re-emerging infectious diseases.

The red panda (Ailurus fulgens) is a distinctive mammal known for its reliance on a diet primarily consisting of bamboo. The gut microbiota and overall health of animals are strongly influenced by diets and environments. Therefore, conducting research to explore the taxonomical and functional variances within the gut microbiota of red pandas exposed to various dietary and environmental conditions could shed light on the dynamic complexities of their microbial communities. In this study, normal fecal samples were obtained from red pandas residing in captive and semi‐free environments under different dietary regimes and used for metabolomic, 16S rRNA, and metagenomic sequencing analysis, with the pandas classified into four distinct cohorts according to diet and environment. In addition, metagenomic sequencing was conducted on mucus fecal samples to elucidate potential etiological agents of disease. Results revealed an increased risk of gastrointestinal diseases in red pandas consuming bamboo shoots due to the heightened presence of pathogenic bacteria, although an increased presence of microbiota‐derived tryptophan metabolites appeared to facilitate intestinal balance. The red pandas fed bamboo leaves also exhibited a decrease in gut microbial diversity, which may be attributed to the antibacterial flavonoids and lower protein levels in leaves. Notably, red pandas residing in semi‐free environments demonstrated an enriched gut microbial diversity. Moreover, the occurrence of mucus secretion may be due to an increased presence of species associated with diarrhea and a reduced level of microbiota‐derived tryptophan metabolites. In summary, our findings substantiate the influential role of diet and environment in modulating the gut microbiota of red pandas, offering potential implications for improved captive breeding practices. [ABSTRACT FROM AUTHOR]

Protection of populations comprising admixed genomes is a challenge under the Endangered Species Act (ESA), which is regarded as the most powerful species protection legislation ever passed in the United States but lacks specific provisions for hybrids. The eastern wolf is a newly recognized wolf-like species that is highly admixed and inhabits the Great Lakes and eastern United States, a region previously thought to be included in the geographic range of only the gray wolf. The U.S. Fish and Wildlife Service has argued that the presence of the eastern wolf, rather than the gray wolf, in this area is grounds for removing ESA protection (delisting) from the gray wolf across its geographic range. In contrast, the red wolf from the southeastern United States was one of the first species protected under the ESA and was protected despite admixture with coyotes. We use whole-genome sequence data to demonstrate a lack of unique ancestry in eastern and red wolves that would not be expected if they represented long divergent North American lineages. These results suggest that arguments for delisting the gray wolf are not valid. Our findings demonstrate how a strict designation of a species under the ESA that does not consider admixture can threaten the protection of endangered entities. We argue for a more balanced approach that focuses on the ecological context of admixture and allows for evolutionary processes to potentially restore historical patterns of genetic variation.

The golden jackal of Africa (Canis aureus) has long been considered a conspecific of jackals distributed throughout Eurasia, with the nearest source populations in the Middle East. However, two recent reports found that mitochondrial haplotypes of some African golden jackals aligned more closely to gray wolves (Canis lupus), which is surprising given the absence of gray wolves in Africa and the phenotypic divergence between the two species. Moreover, these results imply the existence of a previously unrecognized phylogenetically distinct species despite a long history of taxonomic work on African canids. To test the distinct-species hypothesis and understand the evolutionary history that would account for this puzzling result, we analyzed extensive genomic data including mitochondrial genome sequences, sequences from 20 autosomal loci (17 introns and 3 exon segments), microsatellite loci, X- and Y-linked zinc-finger protein gene (ZFX and ZFY) sequences, and whole-genome nuclear sequences in African and Eurasian golden jackals and gray wolves. Our results provide consistent and robust evidence that populations of golden jackals from Africa and Eurasia represent distinct monophyletic lineages separated for more than one million years, sufficient to merit formal recognition as different species: C. anthus (African golden wolf) and C. aureus (Eurasian golden jackal). Using morphologic data, we demonstrate a striking morphologic similarity between East African and Eurasian golden jackals, suggesting parallelism, which may have misled taxonomists and likely reflects uniquely intense interspecific competition in the East African carnivore guild. Our study shows how ecology can confound taxonomy if interspecific competition constrains size diversification.

Macaques (genus Macaca) are the most widely distributed non‐human primates, and their evolutionary history, gene expression profiles, and genetic differences have been extensively studied. However, the DNA methylomes of macaque species are not available in public databases, which hampers understanding of epigenetic differences among macaque species. Epigenetic modifications can potentially affect development, physiology, behavior, and evolution. Here, we investigated the methylation patterns of the Tibetan macaque (M. thibetana; TM), Chinese rhesus macaque (M. mulatta lasiota; CR), and crab‐eating macaque (M. fascicularis; CE) through whole‐genome bisulfite sequencing from peripheral blood. We compared genome‐wide methylation site information for the three species. We identified 12,128 (CR vs. CE), 59,165 (CR vs. TM), and 39,751 (CE vs. TM) differentially methylated regions (DMRs) in the three macaques. Furthermore, we obtained the differentially expressed genes (DEGs) among the three macaque species. The differences between CR and CE were smaller at both the methylome and transcriptome levels than compared with TM (CR vs. TM and CE vs. TM). We also found a change in the density of single nucleotide mutations in DMRs relative to their flanking regions, indicating a potential mechanism through which genomic alterations may modulate methylation landscapes, thereby influencing the transcriptome. Functional enrichment analyses showed the DMR‐related genes were enriched in developmental processes and neurological functions, such as the growth hormone‐related pathway, insulin secretion pathway, thyroid hormone synthesis pathway, morphine addiction, and GABAergic synapses. These differences may be associated with variations in physiology and habitat among the macaques. Our study provides one of the first genome‐wide comparisons of genetic, gene expression, and epigenetic variations across different macaques. Our results should facilitate further research on comparative genomic and genetic differences in macaque species. [ABSTRACT FROM AUTHOR]

Rhesus macaques (Macaca mulatta, RMs) are widely used in sexual maturation studies due to their high genetic and physiological similarity to humans. However, judging sexual maturity in captive RMs based on blood physiological indicators, female menstruation, and male ejaculation behavior can be inaccurate. Here, we explored changes in RMs before and after sexual maturation based on multi-omics analysis and identified markers for determining sexual maturity. We found that differentially expressed microbiota, metabolites, and genes before and after sexual maturation showed many potential correlations. Specifically, genes involved in spermatogenesis (TSSK2, HSP90AA1, SOX5, SPAG16, and SPATC1) were up-regulated in male macaques, and significant changes in gene (CD36), metabolites (cholesterol, 7-ketolithocholic acid, and 12-ketolithocholic acid), and microbiota (Lactobacillus) related to cholesterol metabolism were also found, suggesting the sexually mature males have stronger sperm fertility and cholesterol metabolism compared to sexually immature males. In female macaques, most differences before and after sexual maturity were related to tryptophan metabolism, including changes in IDO1, IDO2, IFNGR2, IL1Β, IL10, L-tryptophan, kynurenic acid (KA), indole-3-acetic acid (IAA), indoleacetaldehyde, and Bifidobacteria, indicating that sexually mature females exhibit stronger neuromodulation and intestinal immunity than sexually immature females. Cholesterol metabolism-related changes (CD36, 7-ketolithocholic acid, 12-ketolithocholic acid) were also observed in female and male macaques. Exploring differences before and after sexual maturation through multi-omics, we identified potential biomarkers of sexual maturity in RMs, including Lactobacillus (for males) and Bifidobacterium (for females) valuable for RM breeding and sexual maturation research. [ABSTRACT FROM AUTHOR]

FASTA and FASTQ are the most widely used biological data formats that have become the de facto standard to exchange sequence data between bioinformatics tools. With the avalanche of next-generation sequencing data, the amount of sequence data being deposited and accessed in FASTA/Q formats is increasing dramatically. However, the existing tools have very low efficiency at random retrieval of subsequences due to the requirement of loading the entire index into memory. In addition, most existing tools have no capability to build index for large FASTA/Q files because of the limited memory. Furthermore, the tools do not provide support to randomly accessing sequences from FASTA/Q files compressed by gzip, which is extensively adopted by most public databases to compress data for saving storage. In this study, we developed pyfastx as a versatile Python package with commonly used command-line tools to overcome the above limitations. Compared to other tools, pyfastx yielded the highest performance in terms of building index and random access to sequences, particularly when dealing with large FASTA/Q files with hundreds of millions of sequences. A key advantage of pyfastx over other tools is that it offers an efficient way to randomly extract subsequences directly from gzip compressed FASTA/Q files without needing to uncompress beforehand. Pyfastx can easily be installed from PyPI (https://pypi.org/project/pyfastx) and the source code is freely available at https://github.com/lmdu/pyfastx. [ABSTRACT FROM AUTHOR]

Canine distemper (CD) is a significant threat to wild and captive giant panda populations. Captive giant pandas are inoculated with canine distemper virus (CDV) vaccination to prevent the infection with the CDV. As an important regulator, microRNA (miRNA) plays a crucial role in regulating gene expression, including in disease immunity. To understand the role of miRNA in immune response to CDV vaccination, we investigated the miRNA expression profile in five giant panda cubs after two inoculations, 21 days apart. A total of 187 conserved miRNAs and 96 novel miRNAs were identified. Among the 187 conserved miRNAs, 29 differentially expressed miRNAs were found postinoculation. The upregulation of miR-16, miR-182, miR-30b, and miR-101 indicated that the innate immune may be enhanced, whereas the upregulation of miR-142 and miR-19a are probably involved in the enhanced cellular immune response. However, the downregulated miR-155 and miR-181a might indicate the giant panda has weak ability to produce antibodies and memory B cells. Integrated analysis of miRNA-messenger RNA (mRNA) found 20 negatively regulated miRNA-mRNA pairs, where downregulated miR-204 might enhance giant panda cub innate immunity by increasing TLR6 expression, and downregulated miR-330 might activate macrophages and regulate the immune response by increasing TMEM106A expression. Our research provides key information for future development to enhance the immune response of giant pandas and potentially improve the survival of captive and wild giant panda populations threatened by CD. [ABSTRACT FROM AUTHOR]

The fall armyworm (Spodoptera frugiperda) is one of the most significant agricultural pests in the world and invaded China in early 2019. We sampled and sequenced RNA-seq data from 15 individuals across different developmental stages. Developmental stages were the larval stage (5th instar larvae and 6th instar larvae), chrysalis stage, and adult stage (female adult and male adult). Individual samples were mainly clustered by developmental stages and we then identified variation between developmental stages of differentially expressed transcripts (DETs). There were 2136 upregulated DETs and 1391 downregulated DETs in the larval stage when comparing larval and chrysalis stages. In the comparison between the chrysalis and adult stages, there were 2033 upregulated DETs and 1391 downregulated DETs in the chrysalis stage. In total, 19,195 abundantly expressed transcripts were obtained and 10% of them were DETs. We then obtained stage-specific DETs to investigate the potential function of the fall armyworm during different developmental stages. We also constructed our annotation background set for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. This indicated that the fall armyworm may undergo active metabolism during its lifespan, even in the chrysalis stage. And it also may experience detoxifying and xenobiotic metabolism throughout its life, especially in the larval stage, which partially explains the difficulty to eradicate using chemical control. Our study is the first insight into the developmental patterns of the fall armyworm and we also provide the fundamental information about enhanced drug resistance at the level of transcriptome. These results are beneficial for a future investigation related to the eradication and/or control stage. [ABSTRACT FROM AUTHOR]

Copy number variation (CNV) can promote phenotypic diversification and adaptive evolution. However, the genomic architecture of CNVs among Macaca species remains scarcely reported, and the roles of CNVs in adaptation and evolution of macaques have not been well addressed. Here, we identified and characterized 1,479 genome-wide hetero-specific CNVs across nine Macaca species with bioinformatic methods, along with 26 CNV-dense regions and dozens of lineage-specific CNVs. The genes intersecting CNVs were overrepresented in nutritional metabolism, xenobiotics/drug metabolism, and immune-related pathways. Population-level transcriptome data showed that nearly 46% of CNV genes were differentially expressed across populations and also mainly consisted of metabolic and immune-related genes, which implied the role of CNVs in environmental adaptation of Macaca. Several CNVs overlapping drug metabolism genes were verified with genomic quantitative polymerase chain reaction, suggesting that these macaques may have different drug metabolism features. The CNV-dense regions, including 15 first reported here, represent unstable genomic segments in macaques where biological innovation may evolve. Twelve gains and 40 losses specific to the Barbary macaque contain genes with essential roles in energy homeostasis and immunity defense, inferring the genetic basis of its unique distribution in North Africa. Our study not only elucidated the genetic diversity across Macaca species from the perspective of structural variation but also provided suggestive evidence for the role of CNVs in adaptation and genome evolution. Additionally, our findings provide new insights into the application of diverse macaques to drug study. [ABSTRACT FROM AUTHOR]

Summary: The Tibetan chicken is a native Chinese breed that lives at high elevations and has adapted to the extreme environmental conditions of the Tibetan Plateau. However, its hypoxic adaptation at the gene expression level is unclear. Here, we sequenced nine lung transcriptomes of the Tibetan chicken at three developmental stages (5 and 42 weeks and 4.5 years). A total of 1.02 billion clean reads were obtained. We identified 16 012 mRNAs and 6898 lncRNAs. The expression of mRNA showed that nine samples were significantly divided into three clusters, with higher correlation and closer relationship between the 5 and 42 week groups. We identified 399 differentially expressed genes (DEGs) between the 5 and 42 week groups, 3532 DEGs between the 5 week and 4.5 year groups, and 3909 DEGs between the 42 week and 4.5 year groups. The up‐regulated DEGs in the 5 week group, compared with 42 week and 4.5 year groups, were enriched in GO terms associated with growth and development, whereas the up‐regulated DEGs in the 4.5 year group were mainly enriched in many metabolic‐related categories. Moreover, the enrichment results with up‐regulated DEGs in the 5 and/or 42 week groups, compared with the 4.5 year group, were associated with hypoxic adaptation, such as oxygen transport, oxygen binding and oxygen carrier activity, and calcium signaling pathway. In addition, we identified 978 high‐correlation lncRNA and protein‐coding gene pairs, and 524 significant neighboring protein‐coding genes were also DEGs. Our results provide new insights into gene expression of lung tissue in Tibetan chickens during the aging process. [ABSTRACT FROM AUTHOR]

Microsatellites are widely distributed throughout nearly all genomes which have been extensively exploited as powerful genetic markers for diverse applications due to their high polymorphisms. Their length variations are involved in gene regulation and implicated in numerous genetic diseases even in cancers. Although much effort has been devoted in microsatellite database construction, the existing microsatellite databases still had some drawbacks, such as limited number of species, unfriendly export format, missing marker development, lack of compound microsatellites and absence of gene annotation, which seriously restricted researchers to perform downstream analysis. In order to overcome the above limitations, we developed PSMD (Pan‐Species Microsatellite Database, http://big.cdu.edu.cn/psmd/) as a web‐based database to facilitate researchers to easily identify microsatellites, exploit reliable molecular markers and compare microsatellite distribution pattern on genome‐wide scale. In current release, PSMD comprises 678,106,741 perfect microsatellites and 43,848,943 compound microsatellites from 18,408 organisms, which covered almost all species with available genomic data. In addition to interactive browse interface, PSMD also offers a flexible filter function for users to quickly gain desired microsatellites from large data sets. PSMD allows users to export GFF3 formatted file and CSV formatted statistical file for downstream analysis. We also implemented an online tool for analysing occurrence of microsatellites with user‐defined parameters. Furthermore, Primer3 was embedded to help users to design high‐quality primers with customizable settings. To our knowledge, PSMD is the most extensive resource which is likely to be adopted by scientists engaged in biological, medical, environmental and agricultural research. [ABSTRACT FROM AUTHOR]

Macaques are the most widely used non-human primates in biomedical research. The genetic divergence between these animal models is responsible for their phenotypic differences in response to certain diseases. However, the macaque single nucleotide polymorphism resources mainly focused on rhesus macaque (Macaca mulatta), which hinders the broad research and biomedical application of other macaques. In order to overcome these limitations, we constructed a database named MACSNVdb that focuses on the interspecies genetic diversity among macaque genomes. MACSNVdb is a web-enabled database comprising ~74.51 million high-quality non-redundant single nucleotide variants (SNVs) identified among 20 macaque individuals from six species groups (muttla , fascicularis , sinica , arctoides , silenus , sylvanus). In addition to individual SNVs, MACSNVdb also allows users to browse and retrieve groups of user-defined SNVs. In particular, users can retrieve non-synonymous SNVs that may have deleterious effects on protein structure or function within macaque orthologs of human disease and drug-target genes. Besides position, alleles and flanking sequences, MACSNVdb integrated additional genomic information including SNV annotations and gene functional annotations. MACSNVdb will facilitate biomedical researchers to discover molecular mechanisms of diverse responses to diseases as well as primatologist to perform population genetic studies. We will continue updating MACSNVdb with newly available sequencing data and annotation to keep the resource up to date. Database URL : http://big.cdu.edu.cn/macsnvdb/ [ABSTRACT FROM AUTHOR]

The American cockroach (Periplaneta americana) is a globally invasive pest that can cause significant economic loss and threaten human health. Although it is abundant and lives in close proximity to humans, few studies have investigated the genetic diversity of P. americana. Our study analyzed 1,053 P. americana and other Periplaneta species' samples from different locations in China and the United States. A traditional tree‐based method using 17 unique mitochondrial COI haplotypes of P. americana and 20 haplotypes of the other Periplaneta species accurately identified P. americana with a barcoding threshold of 5.1%. To identify the population genetic structure of P. americana, we investigated wingless gene and pooled them with obtained mtDNA data for a combined analysis. Although the genetic diversity of the USA group was relatively higher than the China group, the number of haplotypes and alleles of both groups was small. The analysis of molecular variance (AMOVA), intraspecific phylogeny, and haplotype networks indicated that P. americana had very little global genetic differentiation. The weak geographic genetic structure might reflect the human‐mediated dispersal of P. americana. Despite no apparent phylogeographic assignment of mtDNA and nuclear lineages was observed in both BI trees, the integrated COI sequence data identified four distinct P. americana haplotype groups, showing four ancient maternal lineages of P. americana in China and the United States. [ABSTRACT FROM AUTHOR]

The globally distributed American cockroach (Periplaneta americana) is considered a pest, but it has been widely used in traditional Chinese medicine. In the past, the American cockroach's genome and transcriptomes were sequenced, but the differential expression transcripts between developmental stages were unavailable. We performed the de novo assembly and analysis of American cockroach transcriptomes from four developmental stages. Approximately 200 million high-quality paired-end reads were generated by using Illumina Hiseq 2000 sequencer. The assembly produced 291,250 transcripts with an average length of 714 bp. In addition, 38,052 microsatellites and 11,060,020 transposable elements were identified. Based on sequence homology, 53,262 transcripts were annotated. After calculating the expression levels of all the transcripts, we found that 13 transcripts were highly expressed in all the samples and at least two, p10 and actin-related protein 1, played important roles during development. A total of 7954 differentially expressed transcripts (DETs) were identified. The adult had the largest number of DETs when compared to other samples (4818), while the 3rd and 8th larva had the least number of DETs (1332). We performed gene enrichment analysis with the DETs, and some interesting results were detected in the different groups. For example, chitin is the major component of the insect exoskeleton, and the chitin-related genes in larvae and new molted samples had higher expression levels than in adults. In addition, the enrichment analysis detected many chitin-related pathways. Our study performed the first large-scale comparative transcriptomics between the developmental stages of American cockroach, which could provide useful gene expression data for future studies. [ABSTRACT FROM AUTHOR]

The Chinese forest musk deer (Moschus berezovskii ; FMD) is an artiodactyl mammal and is both economically valuable and highly endangered. To investigate the genetic mechanisms of musk secretion and adaptive immunity in FMD, we compared its genome to nine other artiodactyl genomes. Comparative genomics demonstrated that eight positively selected genes (PSGs) in FMD were annotated in three KEGG pathways that were related to metabolic and synthetic activity of musk, similar to previous transcriptome studies. Functional enrichment analysis indicated that many PSGs were involved in the regulation of immune system processes, implying important reorganization of the immune system in FMD. FMD-specific missense mutations were found in two PSGs (MHC class II antigen DRA and ADA) that were classified as deleterious by PolyPhen-2, possibly contributing to immune adaptation to infectious diseases. Functional assessment showed that the FMD-specific mutation enhanced the ADA activity, which was likely to strengthen the immune defense against pathogenic invasion. Single nucleotide polymorphism-based inference showed the recent demographic trajectory for FMD. Our data and findings provide valuable genomic resources not only for studying the genetic mechanisms of musk secretion and adaptive immunity, but also for facilitating more effective management of the captive breeding programs for this endangered species. [ABSTRACT FROM AUTHOR]

The evolutionary history of the stump-tailed macaque ( Macaca arctoides ) and its genetic relationship to other macaques is a subject of continuing controversy. Here, we have reported the first genome sequences of two stump-tailed macaques and one Assamese macaque ( M. assamensis ). Additionally, we have investigated the genetic diversity between macaque species and analyzed ancient hybridization events. Genome-wide analyses demonstrated that the stump-tailed macaque is more closely related to sinica species than to fascicularis/mulatta species. This topology contradicts the mitochondrial sequence-based phylogeny that places the stump-tailed macaque into the fascicularis/mulatta group. However, our results further show that stump-tailed macaques have genetic backgrounds distinct from sinica species, and present evidence of gene flows with rhesus macaques. We suggest that an ancient introgression occurred after stump-tailed macaques diverged from sinica species. The distinct gene flow between proto-arctoides and proto-mulatta resulted in the transfer of rhesus macaque-type mitochondria into proto-arctoides . The rhesus macaque-type mitochondria remained in populations because of genetic drift during the bottleneck. The PSMC results and morphological and geographic evidence are consistent with the mitochondria capture pattern in the stump-tailed macaque. The molecular clock estimates suggest that the mitochondrial transference into stump-tailed macaques occurred 0.4–1.4 million years ago. Furthermore, we detected extensive admixtures between different macaque species, indicating that gene flow has played an important role in the evolutionary history of the genus Macaca . [ABSTRACT FROM AUTHOR]

Background: Whole genome re-sequencing data from dogs and wolves are now commonly used to study how natural and artificial selection have shaped the patterns of genetic diversity. Single nucleotide polymorphisms, microsatellites and variants in mitochondrial DNA have been interrogated for links to specific phenotypes or signals of domestication. However, copy number variation (CNV), despite its increasingly recognized importance as a contributor to phenotypic diversity, has not been extensively explored in canids. Results: Here, we develop a new accurate probabilistic framework to create fine-scale genomic maps of segmental duplications (SDs), compare patterns of CNV across groups and investigate their role in the evolution of the domestic dog by using information from 34 canine genomes. Our analyses show that duplicated regions are enriched in genes and hence likely possess functional importance. We identify 86 loci with large CNV differences between dogs and wolves, enriched in genes responsible for sensory perception, immune response, metabolic processes, etc. In striking contrast to the observed loss of nucleotide diversity in domestic dogs following the population bottlenecks that occurred during domestication and breed creation, we find a similar proportion of CNV loci in dogs and wolves, suggesting that other dynamics are acting to particularly select for CNVs with potentially functional impacts. Conclusions: This work is the first comparison of genome wide CNV patterns in domestic and wild canids using whole-genome sequencing data and our findings contribute to study the impact of novel kinds of genetic changes on the evolution of the domestic dog. [ABSTRACT FROM AUTHOR]

The lineage of the Bar-backed Partridge () was investigated to determine the phylogenetic relationships within Arborophila as the species is centrally distributed within an area covered by the distributions of 22 South-east Asian hill partridge species. The complete mitochondrial genome (mitogenome) of A. brunneopectus was determined and compared with four other hill partridge species mitogenomes. NADH subunit genes are radical in hill partridge mitogenomes and contain the most potential positive selective sites around where variable sites are abundant. Together with 44 other mitogenomes of closely related species, we reconstructed highly resolved phylogenetic trees using maximum likelihood (ML) and Bayesian inference (BI) analyses and calculated the divergence and dispersal history of Arborophila using combined datasets composed of their 13-protein coding sequences. Arborophila is reportedly be the oldest group in Phasianidae whose ancestors probably originated in Asia. A. rufipectus shares a closer relationship with A. ardens and A. brunneopectus compared to A. gingica and A. rufogularis, and such relationships were supported and profiled by NADH dehydrogenase subunit 5 (ND5). The intragenus divergence of all five Arborophila species occurred in the Miocene (16.84~5.69 Mya) when there were periods of climate cooling. We propose that these cooling events in the Miocene forced hill partridges from higher to lower altitudes, which led to geographic isolation and speciation. We demonstrated that the apparently deleterious +1 frameshift mutation in NADH dehydrogenase subunit 3 (ND3) found in all Arborophila is an ancient trait that has been eliminated in some younger lineages, such as Passeriformes. It is unclear of the biological advantages of this elimination for the relevant taxa and this requires further investigation. [ABSTRACT FROM AUTHOR]

Microsatellites are found in taxonomically different organisms, and such repeats are related with genomic structure, function and certain diseases. To characterize microsatellites for macaques, we searched and compared SSRs with 1-6 bp nucleotide motifs in rhesus, cynomolgus and pigtailed macaque. A total of 1395671, 1284929 and 1266348 perfect SSRs were mined, respectively. The most frequent perfect SSRs were mononucleotide SSRs. The most GC-content was in dinucleotide SSRs and the least was in the mononucleotide SSRs. Chromosome size was positively correlated with SSR number and negatively correlated with the relative frequency and density of SSRs. The GC content of chromosome SSRs were negatively correlated with relative frequency of SSRs and GC content of chromosome sequences. The features of microsatellite distribution in assembled genomes of the three species were greatly similar, which revealed that the distributional pattern of microsatellites is probably conservative in genus Macaca. The degenerated number of repeat motifs was found to be different in pentanucleotide and hexanucleotide repeats. Species-specific motifs for each macaque were significantly underrepresented. Overall, SSR frequencies of each chromosome in rhesus macaque were higher than in cynomolgus macaque. The maximum repeat times of mono- to pentanucleotide repeats in cynomolgus macaque was more than other two macaques. These results emphasize the genetic diversity and phylogenetic relationship of genus Macaca species. Our data will be beneficial for comparative genome mapping, understanding the distribution of SSRs and genome structure between these animal models, and provide a foundation for further development and identification of more macaque-specific SSRs. [ABSTRACT FROM AUTHOR]

Complete mitochondrial genomes (mitogenomes) of two cockroach species, Periplaneta australasiae and Neostylopyga rhombifolia, 15,605 bp and 15,711 bp in length, respectively, were determined. As reported for other cockroach mitogenomes, the two mitogenomes possessed typical ancestral insect mitogenome gene composition and arrangement. Only several small intergenic spacers were found: one, which was common in all sequenced cockroach mitogenomes except for the genus Cryptocercus, was between tRNA-Ser (UCN) and ND1 and contained a 7bp highly conserved motif (WACTTAA). Three different types of short tandem repeats in the N. rhombifolia control region (CR) were observed. The homologous alignments of these tandem repeats with other six cockroach mitogenome CRs revealed a low similarity. Three conserved sequence blocks (CSB) were detected in both cockroach mitochondrial CRs. CSB1 was specific for blattinine mitogenomes and was highly conserved with 95% similarity, speculating that this block was a possible molecular synapomorphy for this subfamily. CSB3 located nearby downstream of CSB1 and has more variations within blattinine mitogenomes compared with CSB1. The CSB3 was capable of forming stable stem-loop structure with a small T-stretch in the loop portion. We assessed the influence of four datasets and two inference methods on topology within Orthopteroidea. All genes excluding the third codon positions of PCGs could generate more stable topology, and higher posterior probabilities than bootstrap values were presented at some branch nodes. The phylogenetic analysis with different datasets and analytical methods supported the monophyly of Dictyoptera and supported strongly the proposal that Isoptera should be classified as a family (Termitidae) of the Blattaria. Specifically, Shelfordella lateralis was inserted in the clade Periplaneta. Considering the K2P genetic distance, morphological characters, and the phylogenetic trees, we suggested that S. lateralis should be placed in the genus Periplaneta. [ABSTRACT FROM AUTHOR]

The evolutionary history of macaques, genus Macaca, has been under debate due to the short times of divergence. In this study, maternal, paternal, and biparental genetic systems were applied to infer phylogenetic relationships among macaques and to trace ancient hybridization events in their evolutionary history. Using a PCR display method, 17 newly phylogenetically informative Alu insertions were identified from M. assamensis. We combined presence/absence analysis of 84 Alu elements with mitochondrial genomes as well as nuclear sequences (five autosomal genes, two Y chromosomal genes, and one X chromosomal fragment) to reconstruct a robust macaque phylogeny. Topologies generated from different inherited markers were similar supporting six well defined species groups and a close relationship of M. assamensis and M. thibetana, but differed in the placing of M. arctoides. Both Alu elements and nuclear genes supported that M. arctoides was close to the sinica group, whereas the mitochondrial data clustered it into the fascicularis/mulatta lineage. Our results reveal that a sex-biased hybridization most likely occurred in the evolutionary history of M. arctoides, and suggest an introgressive pattern of male-mediated gene flow from the ancestors of M. arctoides to the M. mulatta population followed by nuclear swamping. According to the estimation of divergence dates, the hybridization occurred around 0.88~1.77 mya (nuclear data) or 1.38~2.56 mya (mitochondrial data). In general, our study indicates that a combination of various molecular markers could help explain complicated evolutionary relationships. Our results have provided new insights into the evolutionary history of macaques and emphasize that hybridization might play an important role in macaque evolution. [ABSTRACT FROM AUTHOR]

Controlling for background demographic effects is important for accurately identifying loci that have recently undergone positive selection. To date, the effects of demography have not yet been explicitly considered when identifying loci under selection during dog domestication. To investigate positive selection on the dog lineage early in the domestication, we examined patterns of polymorphism in six canid genomes that were previously used to infer a demographic model of dog domestication. Using an inferred demographic model, we computed false discovery rates (FDR) and identified 349 outlier regions consistent with positive selection at a low FDR. The signals in the top 100 regions were frequently centered on candidate genes related to brain function and behavior, including LHFPL3, CADM2, GRIK3, SH3GL2, MBP, PDE7B, NTAN1, and GLRA1. These regions contained significant enrichments in behavioral ontology categories. The 3rd top hit, CCRN4L, plays a major role in lipid metabolism, that is supported by additional metabolism related candidates revealed in our scan, including SCP2D1 and PDXC1. Comparing our method to an empirical outlier approach that does not directly account for demography, we found only modest overlaps between the two methods, with 60% of empirical outliers having no overlap with our demography-based outlier detection approach. Demography-aware approaches have lower-rates of false discovery. Our top candidates for selection, in addition to expanding the set of neurobehavioral candidate genes, include genes related to lipid metabolism, suggesting a dietary target of selection that was important during the period when proto-dogs hunted and fed alongside hunter-gatherers. [ABSTRACT FROM AUTHOR]