Characteristics of the chloroplast genome of Dracaena marginata and phylogenetic analysis / 生物工程学报

Dracaena marginata is a widely cultivated horticultural plant in the world, which has high ornamental and medicinal value. In this study, the whole genome of leaves from D. marginata was sequenced by Illumina HiSeq 4000 platform. The chloroplast genome were assembled for functional annotation, sequence characteristics and phylogenetic analysis. The results showed that the chloroplast genome of D. marginata composed of four regions with a size of 154 926 bp, which was the smallest chloroplast genome reported for Dracaena species to date. A total of 132 genes were identified, including 86 coding genes, 38 tRNA genes and 8 rRNA genes. Codon bias analysis found that the codon usage bias was weak and there was a bias for using A/U base endings. 46 simple sequence repeat and 54 repeats loci were detected in the chloroplast genome, with the maximum detection rate in the large single copy region and inverted repeat region, respectively. The inverted repeats boundaries of D. marginata and Dracaena were highly conserved, whereas gene location differences occurred. Phylogenetic analysis revealed that D. serrulata and D. cinnabari form a monophyletic clade, which was the closest relationship and conformed to the morphological classification characteristics. The analysis of the chloroplast genome of D. marginata provides important data basis for species identification, genetic diversity and chloroplast genome engineering of Dracaena.

Genetic and Phenotypic Variation of Campylobacter jejuni NCTC11168 Caused by flhA Mutation during Laboratory Passage / 生物医学与环境科学（英文）

OBJECTIVE@#Campylobacter jejuni NCTC11168 is commonly used as a standard strain for flagellar biosynthesis research. In this report, two distinguished phenotypic isolates (CJ1Z, flhA mutant strain, lawn; CJ2S, flhA complemented strain, normal colony) appeared during laboratory passages for NCTC11168.@*METHODS@#Phenotypic assessments, including motility plates, transmission electron microscopy, biofilm formation assay, autoagglutination assay, and genome re-sequencing for these two isolates (CJ1Z, flhA mutant strain; CJ2S, flhA complemented strain) were carried out in this study.@*RESULTS@#Transmission electron microscopy revealed that the flagellum was lost in CJ1Z. Phenotypic assessments and genome sequencing of the two isolates were performed in this study. The capacity for biofilm formation, colony auto-agglutination, and isolate motility was reduced in the mutant CJ1Z. Comparative genomic analysis indicated a unique native nucleotide insertion in flhA (nt, 2154) that caused the I719Y and I720Y mutations and early truncation in flhA.@*CONCLUSION@#FlhA has been found to influence the expression of flagella in C. jejuni. To the best of our knowledge, this is the first study to describe the function of the C-terminal of this protein.

Identification of a predominant genotype of Mycobacterium tuberculosis in Brazilian indigenous population

After nearly a century of vaccination and six decades of drug therapy, tuberculosis (TB) kills more people annually than any other infectious disease. Substantial challenges to disease eradication remain among vulnerable and underserved populations. The Guarani-Kaiowá people are an indigenous population in Paraguay and the Brazilian state of Mato Grosso do Sul. This community, marginalized in Brazilian society, experiences severe poverty. Like other South American indigenous populations, their TB prevalence is high, but the disease has remained largely unstudied in their communities. Herein, Mycobacterium tuberculosis isolates from local clinics were whole genome sequenced, and a population genetic framework was generated. Phylogenetics show M. tuberculosis isolates in the Guarani-Kaiowá people cluster away from selected reference strains, suggesting divergence. Most cluster in a single group, further characterized as M. tuberculosis sublineage 4.3.3. Closer analysis of SNPs showed numerous variants across the genome, including in drug resistance-associated genes, and with many unique changes fixed in each group. We report that local M. tuberculosis strains have acquired unique polymorphisms in the Guarani-Kaiowá people, and drug resistance characterization is urgently needed to inform public health to ensure proper care and avoid further evolution and spread of drug-resistant TB

Complete chloroplast genome of Sophora alopecuroides (Papilionoideae): molecular structures, comparative genome analysis and phylogenetic analysis

Sophora alopecuroides belongs to the genus Sophora of the family Papilionoideae. It is mainly distributed in the desert and semidesert areas of northern China, and has high medicinal value and ecological function. Previous studies have reported the chemical composition and ecological functions of S. alopecuroides. However, only a few reports are available on the genomic information of S. alopecuroides, especially the chloroplast genome, which greatly limits the study of the evolutionary relationship between other species of Papilionoideae. Here, we report the complete chloroplast genome of S. alopecuroides. The size of the chloroplast genome is 155,207 bp, and the GC content is 36.44%. The S. alopecuroides chloroplast genome consists of 132 genes, including 83 protein-coding genes, 41 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. Phylogenetic analysis revealed the taxonomic position of S. alopecuroidesin Papilionoideae, and the genus Sophora and the genus Ammopiptanthus were highly related. Comparative genomics analysis revealed the gene rearrangement in the evolution of S. alopecuroides. The comparison between S. alopecuroides and the species of the Papilionoideae identified a novel 23 kb inversion between the trnC-GCA and trnF-GAA which occurred before the divergence of Sophora and Ammopiptanthus of Thermopsideae. This study provided an essential data for the understanding of phylogenetic status of S. alopecuroides.

Precision Medicine, Artificial Intelligence, and Genomic Markers in Urology. Do we need to Tailor our Clinical Practice? / Medicina de precisión, inteligencia artificial y marcadores genómicos en urología. ¿Debemos cambiar nuestra práctica clínica?

Precision medicine plays a key role in urological oncology practice nowadays, with the breakthrough of the poly (ADP-ribose) polymerase inhibitors (PARPi), which play a critical role in different DNA damage repair (DDR) pathways, the immune checkpoint inhibitors, the genomic expression profiles and current genome manipulation-directed targeted therapy. Information and technology (IT) are set to change the way we assess and treat patients and should be reviewed and discussed. The aim of the present article is to demonstrate a detailed revision on precision medicine, including novel therapeutic targets, genomic markers, genomic stratification of urological patients, and the top-notch technological breakthroughs that could change our clinical practice We performed a review of the literature in four different databases (PubMed, Embase, Lilacs, and Scielo) on any information concerning prostate, bladder, kidney and urothelial cancer novel treatments with PARPi, immune checkpoint inhibitors (ICIs), targeted therapy with fibroblast growth factor receptor inhibitors (FGFRi), and theranostics with prostate-specific membrane antigen (PSMA) targeted monoclonal antibodies. Artificial intelligence, machine learning, and deep learning algorithm in urological practice were also part of the search. We included all articles written in English, published within the past 7 years, that discussed outstanding therapies and genomics in urological cancer and artificial intelligence applied to urology. Meanwhile, we excluded articles with lack of a clear methodology and written in any other language than English. One-hundred and twenty-six articles of interest were found; of these, 65 articles that presented novel treatments of urological neoplasms, discussed precision medicine, genomic expression profiles and biomarkers in urology, and latest deep learning and machine learning algorithms as well as the use of artificial intelligence in urological practice were selected. A critical review of the literature is presented in the present article. Urology is a constantly changing specialty with a wide range of therapeutic breakthroughs, a huge understanding of the genomic expression profiles for each urological cancer and a tendency to use cutting-edge technology to treat our patients. All of these major developments must be analyzed objectively, taking into account costs to the health systems, risks and benefits to the patients, and the legal background that comes with them. A critical analysis of these new technologies and pharmacological breakthroughs should be made before considering changing our clinical practice. Nowadays, research needs to be strengthened to help us improve results in assessing and treating our patients

La medicina de precisión juega un rol fundamental en la práctica clínica de la urologia oncológica en la actualidad, con el desarrollo de los inhibidores de la poli (ADP-ribosa) polimerasa (PARPi), que juegan un papel fundamental en las distintas vías del reparo del ADN dañado (RAD), los inhibidores del punto de chequeo inmune (ICI), los perfiles de expresión genómicos, y la terapia blanco-dirigida a la manipulación genómica. El desarrollo tecnológico y la informática están cambiando la forma como evaluamos y tratamos a los pacientes, y se debe discutir y revisar a detalle. El objetivo de este artículo es hacer una revisión detallada acerca de la medicina de precisión, genómica, y los avances tecnológicos en nuestro campo. Realizamos una revisión de la literatura en cuatro bases de datos diferentes (PubMed, Embase, Lilacs, y Scielo), buscando cualquier información relacionada con cáncer de próstata, vejiga, riñón y carcinoma urotelial, tratamientos novedosos con PARPi, ICI, terapia-blanco con inhibidores del receptor del factor de crecimiento de los fibroblastos (FGFRi) y teragnósticos con anticuerpos monoclonales dirigidos al antígeno de membrana específico de la próstata (AMEP). Inteligencia artificial, aprendizaje de máquinas y algoritmos de aprendizaje profundo en la práctica urológica también fueron revisados. Incluimos artículos escritos en inglés, publicados dentro de los últimos 7 años, que abordaran terapias novedosas y genómica en cáncer urológico e inteligencia artificial aplicada a la urología. Excluimos artículos con falta de una metodología adecuada y escritos en cualquier idioma diferente al inglés. En total, 126 artículos de interés fueron encontrados, y, de estos seleccionamos 65 artículos que reportaban tratamientos novedosos para neoplasias urológicas, discutían medicina de precisión y perfiles de expresión genómica y bio-marcadores en urología, algoritmos de aprendizaje profundo, aprendizaje de máquina, y el uso de inteligencia artificial en la práctica urológica. Se hizo una revisión crítica de la literatura que se presenta en este artículo. La urología es una especialidad constantemente en cambio, con un gran rango de avances terapéuticos, un gran conocimiento de los perfiles de expresión genómica para cada cáncer urológico, y una tendencia a utilizar tecnología de punta para estudiar y tratar a nuestros pacientes. Todos estos desarrollos se deben analizar objetivamente, y hay que tener en cuenta los costos al sistema de salud, los riesgos y beneficios para los pacientes, y el contexto legal que implica cada uno. Hasta la fecha, estos avances tecnológicos y farmacológicos se deben analizar con cautela antes de vernos en la posición de cambiar nuestra práctica clínica. Se debe fortalecer la investigación médica para mejorar los resultados en el tratamiento y abordaje de nuestros pacientes.

Genome Size Evolution Mediated by Gypsy Retrotransposons in Brassicaceae / 基因组蛋白质组与生物信息学报·英文版

The dynamic activity of transposable elements (TEs) contributes to the vast diversity of genome size and architecture among plants. Here, we examined the genomic distribution and transposition activity of long terminal repeat retrotransposons (LTR-RTs) in Arabidopsis thaliana (Ath) and three of its relatives, Arabidopsis lyrata (Aly), Eutrema salsugineum (Esa), and Schrenkiella parvula (Spa), in Brassicaceae. Our analyses revealed the distinct evolutionary dynamics of Gypsyretrotransposons, which reflects the different patterns of genome size changes of the four species over the past million years. The rate of Gypsy transposition in Aly is approximately five times more rapid than that of Ath and Esa, suggesting an expanding Aly genome. Gypsy insertions in Esa are strictly confined to pericentromeric heterochromatin and associated with dramatic centromere expansion. In contrast, Gypsy insertions in Spa have been largely suppressed over the last million years, likely as a result of a combination of an inherent molecular mechanism of preferential DNA removal and purifying selection at Gypsy elements. Additionally, species-specific clades of Gypsy elements shaped the distinct genome architectures of Aly and Esa.

Leveraging barrel medic genome sequence for the development and use of genomic resources for genetic analysis and breeding in legumes

BACKGROUND: A total of 62,591 cowpea expressed sequence tags (ESTs) were BLAST aligned to the whole-genome sequence of barrel medic (Medicago truncatula) to develop conserved intron scanning primers (CISPs). The efficacy of the primers was tested across 10 different legumes and on different varieties of cowpea, chickpea, and pigeon pea. Genetic diversity was assessed using the same primers on different cowpea genotypes. Singlenucleotide polymorphisms (SNPs) were detected, which were later converted to length polymorphism markers for easy genotyping. CISPs developed in this study were used in tagging resistance to bacterial leaf blight disease in cowpea. RESULTS: A total of 1262 CISPs were designed. The single-copy amplification success rates using these primers on 10 different legumes and on different varieties of cowpea, chickpea, and pigeon pea were approximately 60% in most of the legumes except soybean (47%) and peanut (37%). Genetic diversity analysis of 35 cowpea genotypes using 179 CISPs revealed 123 polymorphic markers with PIC values ranging from 0.05 to 0.59. Potential SNPs identified in cowpea, chickpea, and pigeon pea were converted to PCR primers of various sizes for easy genotyping. Using the markers developed in this study, a genetic linkage map was constructed with 11 linkage groups in cowpea. QTL mapping with 194 F3 progeny families derived from the cross C-152 × V-16 resulted in the identification of three QTLs for resistance to bacterial leaf blight disease. Conclusions: CISPs were proved to be efficient markers to identify various other marker classes like SNPs through comparative genomic studies in lesser studied crops and to aid in systematic sampling of the entire genome for well-distributed markers at low cost

Genome-Wide Assessment of Putative Superoxide Dismutases in Unicellular and Filamentous Cyanobacteria

Abstract Cyanobacteria are photoautotrophic prokaryotes capable to grow in diverse ecological habitats, originated 2.5-3.5 billion years ago and were first to produce oxygen. Since then superoxide dismutases (SOD) acquired great significance due to their ability to catalyze detoxification of byproducts of oxygenic photosynthesis i.e. superoxide radicals. In the present study, we extracted information regarding SODs from species of sequenced cyanobacteria and investigated their diversity, conservation, domain structure, and evolution. 144 putative SOD homologs were identified. Unlike other protein families (ex. serine-threonine kinases) SODs are present in all cyanobacterial species reflecting their significant role in survival. However, their distribution varies fewer (0.01%-0.09%) found in unicellular marine strains whereas abundant (0.02%-0.07%) in filamentous nitrogen-fixing cyanobacteria. They were classified into three major subfamilies according to their domain structures: Fe/MnSOD, Cu/ZnSOD and NiSOD. Interestingly, they lack additional domains as found in proteins of other families however motifs and invariant amino acids typical in eukaryotic SODs were conserved well in these proteins indicating similar catalytic mechanism as eukaryotic SODs. Phylogenetic relationships correspond well with phylogenies based on 16S rRNA and clustering occurs on the basis of structural characteristics such as domain organization. Gene gain-and-loss is insignificant during SOD evolution as evidenced by the absence of additional domain. This study has not only examined an overall background of sequence-structure-function interactions for the SOD gene family but also revealed variation among SOD distribution based on ecophysiological and morphological characters.

Analysis of chloroplast genome and its characteristics of medicinal plant Sophora flavescens / 药学学报

In order to explore the chloroplast genome characteristics of Sophora flavescens and the phylogenetic relationship of the genus, this study used high-throughput sequencing technology to sequence and functionally annotate the chloroplast genome of Sophora flavescens. The results showed that the full length 154 165 bp of Sophora flavescens chloroplast genome showed a typical four-stage structure. The chloroplast genome contains 123 genes, including 77 protein-coding genes, 38 tRNA genes and 8 rRNA genes. Sequence analysis revealed 104 SSR loci, most of which consisted of A and T. In addition, the chloroplast genome codon preference is weak, and the coding region is biased towards the use of A and T bases. A comparative analysis of two different regions of Sophora flavescens chloroplast genome revealed four differential genes. Based on the maximum likelihood method (ML) for phylogenetic analysis of Sophora flavescens and 16 other leguminous, it was found that the relationship between Sophora flavescens and the genus Sophora alopecuroides is the closest. This study provides an important theoretical basis for the genetic variation, breeding and phylogenetic analysis of Sophora flavescens, and has certain reference value.

CNTNAP3 Copy Number Variation and its Significance in Crohn's Disease / 胃肠病学

DNA copy number variation is an important pathogenic factor of human diseases and might be involved in the pathogenesis and pathological process of inflammatory bowel disease (IBD).Aims: To investigate the copy number variation of CNTNAP3 gene and its significance in Crohn''s disease (CD).Methods: A total of 101 active CD patients admitted from Jul.2009 to Dec.2010 at Renji Hospital, School of Medicine, Shanghai Jiao Tong University were enrolled.Eighty healthy subjects were served as controls.Peripheral blood or intestinal mucosa samples of CD patients were collected, and the copy number variation of CNTNAP3 gene was screened and validated by array-based comparative genomic hybridization (aCGH, n=8) and real-time PCR (n=93);expression of CNTNAP3 encoding protein was determined by ELISA (n=55).Results: A large fragment copy number amplification was revealed by aCGH at chromosome 9p13 region (including CNTNAP3 gene) in untreated CD patients.Real-time PCR confirmed that the copy number of CNTNAP3 gene was amplified in peripheral blood of CD patients, especially steroid-naive patients as compared with the normal controls (208 616.4±126 984.7 and 233 453.3±113 520.8 vs.161 750.2 ±53 940.3, P0.05).Furthermore, the plasma CNTNAP3 level in CD patients with amplified copy number was not correlated with the simplified endoscopic score for CD (P>0.05).Conclusions: Copy number amplification of CNTNAP3 gene might be involved in the pathogenesis of CD in Chinese population.Glucocorticoid treatment and smoking might affect the copy number variation of CNTNAP3 gene.Plasma CNTNAP3 level cannot discriminate CD patients from healthy subjects.Conclusions of this study needs to be further demonstrated and discussed.

Comparative genomic analysis of Salmonella type Ⅲsecreted candidate gene yiiG / 基础医学与临床

Objective To study the distribution and evolution of yiiG, a Salmonella gene encoding a candidate type secretedsubstrate .Methods Salmonella genomes were comprehensively screened for yiiG distribution with se-quence alignment strategies .The evolutionary history of yiiG was traced .Comparative genomic analysis was per-formed to study the evolutionary mechanisms of yiiG gene acquisition , loss and duplication .RNA-seq data were combined to analyzing the correlation between yiiG and other virulence factors .A variety of bioinformatic tools were used for discovering the possible type Ⅲsecretion signals .Results yiiG distributed in S.enterica subsp.enterica but variable in other subspecies of S.enterica.No yiiG was found in S.bongori.Besides Salmonella, only a part of Shigella and E.coli strains were detected with yiiG homologs .The genomic locus of yiiG and its adjacency showed conservation among all Salmonella, E.coli and Shigella strains.In most of the serovars of S.enterica subsp.enteri-ca, there was a head-to-head tandem whole yiiG repeat sequence upstream the yiiG gene, which was renamed as yiiGRrc.RNA-seq analysis showed that yiiG gene expression level was highly correlated with T 3SS-related genes . Bioinformatic prediction also indicated the T 3SS effector signals in YiiG N-terminus.Conclusions yiiG represented an ancient genomic locus , which will be a hot spot where rearrangement events frequently happened .The function of yiiG could potentially be related with Salmonella virulence.Finally, a new protein-encoding gene (yiiGRrc) was newly identified that was closely related with yiiG, providing the target for further understanding the composition , function and function variation of yiiG gene family .

Comparative sequence analyses of genome and transcriptome reveal novel transcripts and variants in the Asian elephant Elephas maximus.

The Asian elephant Elephas maximus and the African elephant Loxodonta africana that diverged 5–7 million years ago exhibit differences in their physiology, behaviour and morphology. A comparative genomics approach would be useful and necessary for evolutionary and functional genetic studies of elephants. We performed sequencing of E. maximus and map to L. africana at ~15X coverage. Through comparative sequence analyses, we have identified Asian elephant specific homozygous, non-synonymous single nucleotide variants (SNVs) that map to 1514 protein coding genes, many of which are involved in olfaction. We also present the first report of a high-coverage transcriptome sequence in E. maximus from peripheral blood lymphocytes. We have identified 103 novel protein coding transcripts and 66-long non-coding (lnc)RNAs. We also report the presence of 181 protein domains unique to elephants when compared to other Afrotheria species. Each of these findings can be further investigated to gain a better understanding of functional differences unique to elephant species, as well as those unique to elephantids in comparison with other mammals. This work therefore provides a valuable resource to explore the immense research potential of comparative analyses of transcriptome and genome sequences in the Asian elephant.

Diagnóstico genético preimplantacional: análisis de aneuploidías únicas / Preimplantational genetic diagnosis: single aneuploidies analysis

Introducción: De las causas más conocidas en cuanto a la falta del éxito en el embarazo con tratamientos de reproducción asistida son aquellas relacionadas a las aneuploidías cromosómicas presentes en los embriones. El diagnóstico genético preimplantacional (PGD) es una técnica empleada en reproducción asistida para detectar estas anomalías, seleccionando aquellos que sean cromosómicamente normales, para luego transferirlos al útero de la paciente. Los embriones con aneuploidías únicas podrían tener la capacidad de sobrevivir y lograr la implantación, y por lo tanto, sin diagnóstico previo, estas podrían pasar desapercibidas. Objetivos: Determinar la incidencia de aneuploidías únicas en embriones de buena calidad embrionaria en el día 3 de desarrollo hasta blastocisto. Diseño: Estadístico y experimental. Instituciones: Reprogenetics Latinoamérica y Centro de Reproducción asistida, de la Clínica Concebir. Material Biológico: Muestras de biopsia embrionaria. Metodología: Análisis comparativo de resultados a partir de la evaluación de cada muestra obtenida por biopsia en el día tercero y día quinto de desarrollo embrionario, realizando el PGD por hibridación in situ (FISH) y genómica comparada (aCGH), respectivamente. Resultados: El 62,9% de embriones que presentaron monosomías únicas al tercer día de desarrollo embrionario resultaron ser de 8 células. Pero cuando se evaluó por aCGH en día cinco, 42,3% resultó anormal, y de estos 37,5% perteneció al estadio de 8 células. El índice de monosomías únicas en blastocisto resultó ser 57,9% de un total de 84,2% de aneuploidías únicas. Conclusiones: Los embriones de 8 células en el tercer día de desarrollo embrionario son los más probables de llegar al estadio de blastocisto, así como presentar aneuploidías únicas.

Background: Known causes of unsuccessful pregnancy in couples undergoing assisted reproduction treatment include embryo aneuploidies. Preimplantation genetic diagnosis (PGD) is a technique used in assisted reproduction in order to detect these abnormalities, select embryos chromosomally normal and subsequently transfer to the patients’ uterus. Embryos with single aneuploidies may have the ability to survive and achieve unnoticed implantation. Objectives: To determine incidence of single aneuploidies in good quality embryos in third day of development to blastocyst. Design: Statistical and experimental study. Setting: Reprogenetics Latin-America and Assisted Reproduction Center - Concebir. Biologic material: Samples of embryo biopsies. Methods: Comparative analysis of results from evaluation of each sample obtained by embryo biopsy on the third and fifth days of embryonic development, performing PGD by respectively in situ hybridization (FISH) and comparative genomics (aCGH). Results: On third day of embryonic development 62.9% of embryos with single monosomy had 8-cell morphology. Though when evaluated by aCGH in the blastocyst stage 42.3% were abnormal and 37.5% of these belonged to the 8-cell stage. Single monosomies index in the blastocyst stage was 57.9% in 84.2% of single aneuploidies. Conclusions: Eight-cell embryos on the third day of embryonic development are most likely to reach blastocyst stage and have single aneuploidies.

Evolution and structural analysis of interleukin-17 / 第二军医大学学报

Objective To investigate the origin and protein structures of vertebrate interleukin-17 (IL-17) genes via phylogenetic and bioinformatic approaches. Methods All the known IL-17 protein sequences of human, zebrafish and amphioxus were retrieved from the National Center for Biotechnology Information (NCBI) and Joint Genome Institute (JGI) databases. Also, partial IL-17 sequences from seven other model organisms were collected from several specific databases. MEGA software package was used to reconstruct a phylogenetic tree for these sequences and MODELLER software was used to predict IL-17 three-dimensional models of zebrafish, amphioxus, ciona and caenorhabditis, and these models were then compared with the known crystal structure of human IL-17F. Results Although all the IL-17 protein sequences contained four conservative cysteine residues that may be involved in the formation of a typical cysteine knot, amphioxus IL-17 revealed two different distribution patterns, with one similar to that of vertebrates and one unique to amphioxus. Phylogenetic analysis and cysteine analysis showed that amphioxus genome had no ortholog of vertebrate IL-17 genes, but urochordate ciona genome had it. The structural comparison result of our three-dimensional models supported the phylogenetic tree. Conclusion Amphioxus IL-17 might be the divergent point in the IL-17 evolution. The ortholog of vertebrate IL-17 genes might first appear in urochordates.

Study of Modern Human Evolution via Comparative Analysis with the Neanderthal Genome

Many other human species appeared in evolution in the last 6 million years that have not been able to survive to modern times and are broadly known as archaic humans, as opposed to the extant modern humans. It has always been considered fascinating to compare the modern human genome with that of archaic humans to identify modern human-specific sequence variants and figure out those that made modern humans different from their predecessors or cousin species. Neanderthals are the latest humans to become extinct, and many factors made them the best representatives of archaic humans. Even though a number of comparisons have been made sporadically between Neanderthals and modern humans, mostly following a candidate gene approach, the major breakthrough took place with the sequencing of the Neanderthal genome. The initial genome-wide comparison, based on the first draft of the Neanderthal genome, has generated some interesting inferences regarding variations in functional elements that are not shared by the two species and the debated admixture question. However, there are certain other genetic elements that were not included or included at a smaller scale in those studies, and they should be compared comprehensively to better understand the molecular make-up of modern humans and their phenotypic characteristics. Besides briefly discussing the important outcomes of the comparative analyses made so far between modern humans and Neanderthals, we propose that future comparative studies may include retrotransposons, pseudogenes, and conserved non-coding regions, all of which might have played significant roles during the evolution of modern humans.

Xylella fastidiosa comparative genomic database is an information resource to explore the annotation, genomic features, and biology of different strains

The Xylella fastidiosa comparative genomic database is a scientific resource with the aim to provide a user-friendly interface for accessing high-quality manually curated genomic annotation and comparative sequence analysis, as well as for identifying and mapping prophage-like elements, a marked feature of Xylella genomes. Here we describe a database and tools for exploring the biology of this important plant pathogen. The hallmarks of this database are the high quality genomic annotation, the functional and comparative genomic analysis and the identification and mapping of prophage-like elements. It is available from web site http://www.xylella.lncc.br.

Comparison of Yersinia pestis genomes from a new natural foci in China / 中国地方病学杂志

Objective Measurement and analysis of the complete genome sequences of Yersinia Pestis from a new plague natural foci and adjacent foci in China, to know the genetic relationship among the epidemic strain isolated in Yulong (D 106004) and Jianchuan strains (D 182038) and the Tibetan strain ( Z 176003 ). Methods Three complete genome sequences were sequenced using the whole-genome shotgun and Solexa method and comparative genomics analysis was done among the three sequences. Genome comparative analysis among the coding sequences was done by BLAST software, SNPs finding was done by the program, genome rearrangements were analyzed using MAUVE software. Results All of the genomes of Yersinia pestis strains D182038, D106004 and Z176003 consist of a single circular chromosome and three virulence plasmids, pMT1, pCD1 and pPCP1. They had similar characteristics in chromosome and plasmid features, and there were no significant difference in coming sequence (CDS) of the cluster of orthologous groups of proteins (COG) functional classification and the number of insertion sequence in the three strains (x2 =3.03, 0.257, all P ＞ 0.05). The comparative genomics results showed that the three bacteria had 2882 genes with 100％ homology, of 3636 genes predicted in D106004, 2994 were identical with D182038's and 3113 with Z176003's, and of which 240 had 90％ homology with D182038's and 200 with Z176003 's. Synonymous single nucleotide polymorphisms(sSNPs) were 59 and 68, and non-synonymous SNPs(nsSNPs) were 104 and 203 between strains D106004 and Z176003/D182038. There were 11 segments rearrangements between D106004 and Z176003, which was less than 16 segments rearrangements between D106004 and D182038. ConclusionsThe three strains are highly homologous, the Yulong strain has more similarity with Tibet strain than with Jianchuan strain, the strain from Yulong foci may be evolved from Tibet foci.

Strain diversity within Mycobacterium avium subspecies paratuberculosis — A review.

Mycobacterium avium subspecies paratuberculosis (MAP), is the etiological agent of Johne’s disease (or paratuberculosis) in animals and has also been linked with Crohn’s disease of human beings. Extreme fastidious nature of the organism (MAP) has hampered studies on diversity within the organism. Studies based on phenotypic properties like growth rate, pigmentation, lipid profile etc., are unable to provide complete information on diversity of MAP organism in nature. However, with the advent of molecular assays (IS900 RFLP, PFGE, IS1311 PCR-REA, SSR typing, VNTR typing etc.) in last 2 decades, progress has been made to differentiate MAP strains. MAP isolates have been classified into various types and subtypes using these molecular tools. Optimization of these typing assays has led to generation of new information about MAP strains, subtypes, their comparative genomics, relative evolution, comparative virulence etc. Knowledge of strain diversity is important for better understanding of molecular and sero-epidemiology, infection and patho-biology, vaccine development and planning control strategies. The present review provides available information on MAP strains, host adaptations, their virulence, comparative genomics, relative genetic evolution and differentiation.

Identificação de genes com expressão modulada por estreptomicina e de genes associados à virulência e patogenicidade em Xylella fastidiosa / Identification of genes modulated by streptomycin and of genes related to virulence and pathogenicity in Xylella fastidiosa

Em concentrações subletais, agentes antimicrobianos modulam a expressão gênica bacteriana, sendo que o conjunto de genes que é modulado depende tanto da cepa bacteriana, como da natureza do agente antimicrobiano. Neste trabalho, avaliamos o perfil de expressão gênica de Xylella fastidiosa cepa 9a5c em resposta ao tratamento por até 60 minutos com dose subletal do antibiótico estreptomicina. Esta é uma cepa virulenta, originalmente isolada de laranjeiras com sintomas de clorose variegada dos citros. A hibridização de microarranjos de DNA representando 2608 das 2848 sequências codificadoras (CDS) previamente anotadas no genoma desta cepa, revelou que 136 CDS apresentaram expressão gênica diferencial em resposta à exposição à estreptomicina, sendo que destas 109 foram negativamente moduladas e 27 positivamente moduladas. Realizamos, também, ensaios de PCR quantitativo precedido de transcrição reversa (RTqPCR) de 21 CDS para confirmar a modulação observada na análise global da expressão gênica. O perfil de expressão gênica de X. fastidiosa em resposta à estreptomicina foi analisado de forma integrada com outros perfis de expressão gênica desta bactéria. Entre as CDS positivamente moduladas, destacamos aquelas codificadoras das chaperoninas GroEL e GroES, que estão associadas a resposta de choque térmico, e CDS associadas à tradução, tais como proteínas ribossomais e fatores de tradução. Interessantemente, a exposição à estreptomicina induz a expressão da CDS que codifica poligalacturonase, que é um fator de virulência em algumas cepas de X. fastidiosa. Por outro lado, o tratamento com estreptomicina promoveu a modulação negativa de CDS relacionadas à formação e manutenção de biofilme ao contrário do observado quando estas bactérias foram submetidas ao tratamento com gomesina, um peptídeo antimicrobiano. O conjunto destas observações sugere que a exposição à dose subletal de estreptomicina possa promover um fenótipo de maior virulência, contrariamente ao efeito...

At sublethal concentrations, antimicrobials compounds modulate bacterial gene expression and the gene set that is modulated depends not only on the bacterial strain but also on the nature of antimicrobial agent. In this study, we evaluated changes in gene expression profile of Xylella fastidiosa strain 9a5c exposed up to 60 min to sublethal concentration of streptomycin. This a virulent strain originally isolated from orange trees with symptoms of citrus variegated chlorosis. Hybridization of DNA microarrays representing 2,608 out of 2848 coding sequences (CDS) previously annotated in strain 9a5c genome revealed 136 CDS differentially expressed upon streptomycin treatment. Of which 109 were down-regulated and 27 up-regulated. Differential expression for a subset of 21 CDS was further evaluated by reverse transcriptionquantitative PCR (RT-qPCR). In addition, we performed an integrated analysis of the gene expression profile of X. fastidiosa in response to streptomycin along with other gene expression profiles available for this bacterium. Among the up-regulated CDS, we highlight those encoding chaperonins GroEL and GroES, which are associated with heat shock response, and those CDS related to translation, such as ribosomal proteins and translation factors. Interestingly, exposure to streptomycin induces the expression of a CDS encoding polygalacturonase, which is a virulence factor for some X. fastidiosa strains. Furthermore, treatment with streptomycin down-regulates some CDS related to biofilm formation oppositely to treatment with gomesin, an antimicrobial peptide. Together, these observations suggest that exposure to sublethal dose of streptomycin might promote a higher virulent phenotype, in contrast to the effect previously observed with gomesin. In the present work, we also describe the pyrosequencing of J1a12 genome, a X. fastidiosa strain that exhibits a less virulent phenotype in citrus and tobacco if compared to strain 9a5c. A comparison of genome...

Characterization & evolutionary analysis of human CD36 gene.

Background and objectives: Understanding evolutionary genetic details of immune system genes responsible for infectious diseases is of prime importance concerning disease pathogenecity. Considering malaria as a devastating disease in the world including India, detail evolutionary understanding on human immune system gene is essential. The primary aim of this study was to initiate work on one such gene, the human CD36 gene responsible in malaria pathogenesis. Methods: DNA sequences of the human CD36 gene was retrieved from public domain and fifi ne-scale details were characterized. Both comparative and evolutionary analyses were performed with sequences from six other taxa (5 mammalian one avian) where CD36 homologs are present. Different statistical analyses were also performed. Results: Differential distribution in number and length of exons and introns was detected in CD36 gene across seven taxa. The CpG islands were also found to be distributed unevenly across the gene and taxa. Neighbour-joining tree was constructed and it was observed that the chimpanzee and human are diverged at the CD36 gene relatively recently. The chicken, Gallus gallus was found to be diverged from rest of the taxa signifi cantly. Also copy number variation was observed across different taxa. Interpretation & conclusions: Comparative genomic study of a human immune system gene CD36 show relationships among different taxa at the evolutionary level. The information can be of help to study genetic diversity in malaria endemic zones and to correlate it with malaria pathogenecity.