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This study investigates the genomic landscape of Sika deer populations, emphasizing the detection and characterization of runs of homozygosity (ROH) and their contribution towards components of fitness. Using 85,001 high-confidence SNPs, the investigation into ROH distribution unveiled nuanced patterns of autozygosity across individuals especially in 2 out of the 8 farms, exhibiting elevated ROH levels and mean genome coverage under ROH segments. The prevalence of shorter ROH segments (0.5-4 Mb) suggests historical relatedness and potential selective pressures within these populations. Intriguingly, despite observed variations in ROH profiles, the overall genomic inbreeding coefficient (FROH) remained relatively low across all farms, indicating a discernible degree of genetic exchange and effective mitigation of inbreeding within the studied Sika deer populations. Consensus ROH (cROH) were found to harbor genes for important functions viz., EGFLAM gene which is involved in the vision function of the eye, SKP2 gene which regulates cell cycle, CAPSL involved in adipogenesis, SPEF2 which is essential for sperm flagellar assembly, DCLK3 involved in the heat stress. This first ever study on ROH in Sika deer, to shed light on the adaptive role of genes in these homozygous regions. The insights garnered from this study have broader implications in the management of genetic diversity in this vulnerable species.
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Despite the widespread occurence of Newcastle disease virus (NDV) in different avian species, there has been scanty reports on genetic characterization of NDV strains from wild birds in India. During 2017-18, a total of forty eight cloacal swab samples were collected from apparently healthy migratory birds (painted storks, n = 32 and spot-billed pelicans, n = 16) at the Telineelapuram bird sanctuary of Andhra Pradesh, India. NDV was isolated from a spot-billed pelican (NDV/Pelican/Telineelapuram/2018) which is genetically identical to that isolated from a naturally infected backyard chicken flock (NDV/Chicken/SKLM-1/2018). The isolates are found to be velogenic based on mean death time, intracerebral pathogenicity index and the putative fusion protein cleavage site (112R-R-R-K-R-F117). Phylogenetic analysis based on full-length fusion gene classified the isolates into genotype XIII, sub-genotype 2.2, however these isolates demonstrated multiple amino acid substitutions in the critical domains of F and HN proteins. The pelican strain (MIG-9) was tested for its pathogenic and transmission potential in three-weeks-old broiler chickens and the isolate proved to be highly virulent to chickens. To the best of our knowledge, this is the first evidence for the role of spot-billed pelicans in the maintenance of virulent NDV and its transmission to chickens in India. This study further highlights the role of wild birds in NDV transmission and the need for enhanced biosecurity in commercial poultry operations. Keywords: Newcastle disease virus; Pelecanus philippensis; chicken; transmission; pathogenicity; India.
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Doença de Newcastle , Doenças das Aves Domésticas , Animais , Animais Selvagens/genética , Galinhas , Genoma Viral , Genótipo , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle , FilogeniaRESUMO
Various candidate genes have been reported to affect milk yield and composition in dairy cattle. A non-synonymous mutation in the DGAT1 gene, i.e., K232A was reported to have a strong association with milk yield and milk composition of Bos taurus. A study has been undertaken on 502 unrelated individuals belonging to indigenous Ongole cattle, crossbred cattle, and Murrah buffaloes from the Indian sub-continent with the objective to determine the polymorphism of the K232A locus and their association with milk yield and composition. Typing DGAT1 K232A allelic variation by PCR-RFLP using CfrI restriction enzyme revealed three genotypes in crossbred cattle. Genotype KK was more prevalent (0.60) in Jersey crossbred, whereas in Holstein Friesian crossbred it was KA genotype (0.48). In Ongole cattle and Murrah buffaloes, the locus did not exhibit polymorphism. The least-square mean of milk yields pooled over lactations across the DGAT1 variants was significantly (P < 0.05) higher among the homozygous (AA) genotypes, both in Jersey crossbred and HF crossbred cattle after adjusting for the effects of farm, parity, and season. The fat, SNF, and protein content values of AA genotypes were less than the KK genotypes in both the genetic groups (P > 0.05). The fixation of the DGAT1K allele at the locus in Bos indicus cattle and Bubalus bubalis in the present study did not support its use as a reliable universal marker for milk production and composition traits.
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Búfalos , Leite , Animais , Búfalos/genética , Bovinos/genética , Diacilglicerol O-Aciltransferase/genética , Feminino , Genótipo , Índia , Lactação , MutaçãoRESUMO
The aim of this study was to investigate the probiotic potential of autochthonous Lactobacillus species isolated from buffalo calves against multidrug-resistant Escherichia coli. A total of 252 rectal swabs were collected from healthy neonatal buffalo calves under 30 days old from six districts of Andhra Pradesh, India in a completely randomized design from August 2019 to August 2021, of which 190 Lactobacillus strains were isolated based on cultural, morphological, biochemical and molecular tests. Out of 190 isolates, 57 showed high levels of auto-aggregation (> 80.00%) and hydrophobicity (> 60.00%) and 51 of the 57 isolates had a zone of inhibition greater than 15.00 mm in diameter against multidrug-resistant E. coli in an Agar well diffusion assay. Among the 51 isolates, 36 were found to be acid and bile tolerant and showed varying levels of sensitivity to antibiotics such as erythromycin, clindamycin, tetracycline, chloramphenicol, and ampicillin. Among the 36 isolates, Limosilactobacillus reuteri 178, L. reuteri 209, L. fermentum 182, L. fermentum 211, and Lactiplanti-bacillus plantarum 34 were non-hemolytic, and none of the isolates were able to hydrolyse gelatine. Therefore, these five autochthonous Lactobacillus species may be used in probiotic or synbiotic formulations against multidrug resistant E. coli in buffalo calves.
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BACKGROUND: The Drosophila X-chromosome shows a significant underrepresentation of genes with male-biased gene expression (demasculinization). This trend is matched by retrogenes, which typically have a male biased gene expression pattern and show a significant movement bias from X-chromosomes to autosomes. It is currently assumed that these patterns are best explained by selection, either mediated by male meiotic sex chromosome inactivation (MSCI) or sexually antagonistic forces. We scrutinized the evolutionary dynamics of retroposition by focusing on retrogenes for which the parental copy has degenerated. RESULTS: Consistent with a functional substitution of the degenerated gene by the retrogene, patterns of sequence evolution and gene expression were similar between retroposed and parental genes. Like previous studies, our set of retrogenes showed a significant movement off the X-chromosome. In contrast to data sets where retroposition caused gene duplication, the genes in our study showed primarily female-biased or unbiased gene expression. CONCLUSIONS: Based on our results, the biased transposition pattern cannot be explained by MSCI and probably not by sexual antagonism. Rather, we propose that the movement away from the X-chromosome represents a general property of retroposition in Drosophila.
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Drosophila/genética , Genoma de Inseto , Retroelementos , Animais , Cromossomos , Culicidae/genética , Feminino , Genes de Insetos , Genes Ligados ao Cromossomo X , MasculinoRESUMO
BACKGROUND: The origin of functional innovation is among the key questions in biology. Recently, it has been shown that new genes could arise from non-coding DNA and that such novel genes are often involved in male reproduction. RESULTS: With the aim of identifying novel genes, we used the technique "generation of longer cDNA fragments from serial analysis of gene expression (SAGE) tags for gene identification (GLGI)" to extend 84 sex-biased 3'end SAGE tags that previously could not be mapped to the D. pseudoobscura transcriptome. Eleven male-biased and 33 female-biased GLGI fragments were obtained, of which 5 male-biased and 3 female-biased tags corresponded to putatively novel genes. This excess of novel genes with a male-biased gene expression pattern is consistent with previous results, which found novel genes to be primarily expressed in male reproductive tissues. 5' RACE analysis indicated that these novel transcripts are very short in length and could contain introns. Interspecies comparisons revealed that most novel transcripts show evidence for purifying selection. CONCLUSION: Overall, our data indicate that among sex-biased genes a considerable number of novel genes (approximately 2-4%) exist in D. pseudoobscura, which could not be predicted based on D. melanogaster gene models.
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Drosophila/genética , Genes de Insetos , Animais , DNA Complementar/metabolismo , Drosophila/classificação , Evolução Molecular , Feminino , Masculino , Dados de Sequência Molecular , Caracteres Sexuais , Especificidade da EspécieRESUMO
BACKGROUND: Domestication of chicken is believed to have occurred in Southeast Asia, especially in Indus valley. However, non-inclusion of Indian red jungle fowl (RJF), Gallus gallus murghi in previous studies has left a big gap in understanding the relationship of this major group of birds. In the present study, we addressed this issue by analyzing 76 Indian birds that included 56 G. g. murghi (RJF), 16 G. g. domesticus (domestic chicken) and 4 G. sonneratii (Grey JF) using both microsatellite markers and mitochondrial D-loop sequences. We also compared the D-loop sequences of Indian birds with those of 779 birds obtained from GenBank. RESULTS: Microsatellite marker analyses of Indian birds indicated an average FST of 0.126 within G. g. murghi, and 0.154 within G. g. domesticus while it was more than 0.2 between the two groups. The microsatellite-based phylogenetic trees showed a clear separation of G. g. domesticus from G. g. murghi, and G. sonneratii. Mitochondrial DNA based mismatch distribution analyses showed a lower Harpending's raggedness index in both G. g. murghi (0.001515) and in Indian G. g. domesticus (0.0149) birds indicating population expansion. When meta analysis of global populations of 855 birds was carried out using median joining haplotype network, 43 Indian birds of G. g. domesticus (19 haplotypes) were distributed throughout the network sharing haplotypes with the RJFs of different origins. CONCLUSION: Our results suggest that the domestication of chicken has occurred independently in different locations of Asia including India. We found evidence for domestication of Indian birds from G. g. spadiceus and G. g. gallus as well as from G. g. murghi, corroborating multiple domestication of Indian and other domestic chicken. In contrast to the commonly held view that RJF and domestic birds hybridize in nature, the present study shows that G. g. murghi is relatively pure. Further, the study also suggested that the chicken populations have undergone population expansion, especially in the Indus valley.
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Animais Domésticos/genética , Galinhas/genética , DNA Mitocondrial/genética , Repetições de Microssatélites/genética , Animais , Sequência de Bases , Galinhas/classificação , Evolução Molecular , Variação Genética , Haplótipos , Índia , Dados de Sequência Molecular , Filogenia , Análise de Componente Principal , Alinhamento de SequênciaRESUMO
Sexually dimorphic traits are often subject to diversifying selection. Genes with a male-biased gene expression also are probably affected by sexual selection and have a high rate of protein evolution. We used SAGE to measure sex-biased gene expression in Drosophila pseudoobscura. Consistent with previous results from D. melanogaster, a larger number of genes were male biased (402 genes) than female biased (138 genes). About 34% of the genes changed the sex-related expression pattern between D. melanogaster and D. pseudoobscura. Combining gene expression with protein divergence between both species, we observed a striking difference in the rate of evolution for genes with a male-biased gene expression in one species only. Contrary to expectations, D. pseudoobscura genes in this category showed no accelerated rate of protein evolution, while D. melanogaster genes did. If sexual selection is driving molecular evolution of male-biased genes, our data imply a radically different selection regime in D. pseudoobscura.
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Drosophila/genética , Evolução Molecular , Genes de Insetos , Proteínas de Insetos/genética , Substituição de Aminoácidos , Animais , Cromossomos/química , Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Expressão Gênica , Biblioteca Genômica , Proteínas de Insetos/metabolismo , Masculino , Fatores Sexuais , SinteniaRESUMO
BACKGROUND: Molecular characterization of cattle breeds is important for the prevention of germplasm erosion by cross breeding. The Indian zebu cattle have their significant role in evolution of present day cattle breeds and development of some of the exotic breeds. Microsatellites are the best available molecular tools for characterization of cattle breeds. The present study was carried out to characterize two Indian cattle breeds, Ongole and Deoni, using microsatellite markers. RESULTS: Using 5 di- and 5 tri-nucleotide repeat loci, 17 Ongole and 13 Deoni unrelated individuals were studied. Of the ten loci, eight revealed polymorphism in both the breeds. The di-nucleotide repeat loci were found to be more polymorphic (100%) than tri-nucleotide repeat loci (60%). A total of 39 polymorphic alleles were obtained at 4.5 alleles per locus in Ongole and 4.1 in Deoni. The average expected heterozygosity was 0.46 (+/-0.1) and 0.50 (+/-0.1) in Ongole and Deoni breeds, respectively. The PIC values of the polymorphic loci ranged from 0.15 to 0.79 in Ongole and 0.13 to 0.80 in Deoni breeds. Six Ongole specific and three Deoni specific alleles were identified. The two breeds showed a moderate genetic relationship between themselves with a FST value of 0.117 (P = 0.01). CONCLUSIONS: This preliminary study shows that microsatellite markers are useful in distinguishing the two zebu breeds namely, Ongole and Deoni. Further studies of other zebu breeds using many microsatellite loci with larger sample sizes can reveal the genetic relationships of Indian breeds.
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Genética , Repetições de Microssatélites/genética , Animais , Cruzamento , Bovinos , Cruzamentos Genéticos , Evolução Molecular , Índia , Projetos Piloto , Polimorfismo Genético/genéticaRESUMO
Massively parallel sequencing holds great promise for expression profiling, as it combines the high throughput of SAGE with the accuracy of EST sequencing. Nevertheless, until now only very limited information had been available on the suitability of the current technology to meet the requirements. Here, we evaluate the potential of 454 sequencing technology for expression profiling using Drosophila melanogaster. We show that short (< approximately 80 bp) and long (> approximately 300-400 bp) cDNA fragments are under-represented in 454 sequence reads. Nevertheless, sequencing of 3' cDNA fragments generated by nebulization could be used to overcome the length bias of the 454 sequencing technology. Gene expression measurements generated by restriction analysis and nebulization for fragments within the 80- to 300-bp range showed correlations similar to those reported for replicated microarray experiments (0.83-0.91); 97% of the cDNA fragments could be unambiguously mapped to the genomic DNA, demonstrating the advantage of longer sequence reads. Our analyses suggest that the 454 technology has a large potential for expression profiling, and the high mapping accuracy indicates that it should be possible to compare expression profiles across species.
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Mapeamento Cromossômico , DNA Complementar/genética , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Genoma de Inseto/genética , Análise de Sequência de DNA , Animais , Bases de Dados de Ácidos Nucleicos , Drosophila melanogasterRESUMO
Molecular phylogeny of some of the economically important silkmoths was derived using three mitochondrial genes, 12S rRNA, 16S rRNA, and COI, and the control region (CR). Maximum likelihood (ML) analyses showed two distinct clades, one consisting of moths from Bombycidae family and the other from Saturniidae family. The mitochondrial CR showed length polymorphisms with indels. The ML analyses for complete mitochondrial genome sequences of Bombyx mori (strains Aojuku, C108, Backokjam, and Xiafang), Japanese and Chinese strains of B. mandarina (Japanese mandarina and Chinese mandarina) and, Antheraea pernyi revealed two distinct clades, one comprising of B. mori strains and the other with B. mandarina, and A. pernyi forming an outgroup. Pairwise distances revealed that all of the strains of B. mori studied are closer to Chinese than to Japanese mandarina. Phylogenetic analyses based on whole mitochondrial genome sequences, the finding of a tandem triplication of a 126bp repeat element only in Japanese mandarina, and chromosome number variation in B. mandarina suggest that B. mori must have shared its recent common ancestor with Chinese mandarina. Another wild species of the Bombycidae family, Theophila religiosa, whose phylogenetic status was not clear, clustered together with the other bombycid moths in the study. Analysis of the interspecific hybrid, A. proylei gave evidence for paternal inheritance of mitochondrial DNA.