Genetics and Molecular Biology, Volume: 44, Issue: 3, Published: 2021
  • Spontaneous chromosomal instability in peripheral blood lymphocytes from two molecularly confirmed Italian patients with Hereditary Fibrosis Poikiloderma: insights into cancer predisposition Human and Medical Genetics

    Roversi, Gaia; Colombo, Elisa Adele; Magnani, Ivana; Gervasini, Cristina; Maggiore, Giuseppe; Paradisi, Mauro; Larizza, Lidia

    Abstract in English:

    Abstract Two Italian patients with the initial clinical diagnosis of Rothmund-Thomson syndrome were negative for RECQL4 mutations but showed in peripheral blood cells a spontaneous chromosomal instability significantly higher than controls. Revisiting after time their clinical phenotype, the suggestive matching with the autosomal dominant syndrome Poikiloderma, Hereditary Fibrosing with Tendon Contracture, Myopathy and Pulmonary fibrosis (POIKTMP) was confirmed by identification of the c.1879A>G (p.Arg627Gly) alteration in FAM111B. We compare the overall clinical signs of our patients with those of reported carriers of the same mutation and present the up-to-date mutational repertoire of FAM111B and the related phenotypic spectrum. Our snapshot highlights the age-dependent clinical expressivity of POIKTMP and the need to follow-up patients to monitor the multi-tissue impairment caused by FAM111B alterations. We link our chromosomal instability data to the role of FAM111B in cancer predisposition, pointed out by its implication in DNA-repair pathways and the outcome of pancreatic cancer in 2 out of 17 adult POIKTMP patients. The chromosomal instability herein highlighted well connects POIKTMP to cancer-predisposing syndromes, such as Rothmund-Thomson which represents the first hereditary poikiloderma entering in differential diagnosis with POIKTMP.
  • MiR-181b serves as diagnosis and prognosis biomarker in severe community-acquired pneumonia Human and Medical Genetics

    Li, Qiaolian; Wu, Tingting; Li, Song

    Abstract in English:

    Abstract Severe community-acquired pneumonia (SCAP) is a common critical disease in the intensive care unit (ICU). This study aims to evaluate the clinical significance of miR-181b in SCAP, which has been revealed to be dysregulated in acute respiratory distress syndrome events due to SCAP. There were 50 SCAP patients and 26 healthy volunteers were recruited in this study. The expression of miR-181b was detected by RT-qPCR and the difference between SCAP and healthy controls was evaluated. The diagnosis and prognosis value of miR-181b was assessed by the receiver operating characteristics (ROC), Kaplan-Meier, and Cox regression analysis. miR-181b was significantly downregulated in SCAP compared with healthy controls. The downregulation of miR-181b showed a significant association with the white blood cell count, absolute neutrophils, and the C-reactive protein of patients. The downregulation of miR-181b could distinguish SCAP patients from healthy controls and predicate the poor prognosis of SCAP patients. Downregulated miR-181b serves as a diagnosis and prognosis biomarker for SCAP, which may be useful biological information for the early detection and risk estimation of SCAP.
  • Chromosomal aberrations after induced pluripotent stem cells reprogramming Human and Medical Genetics

    Vaz, Isadora May; Borgonovo, Tamara; Kasai-Brunswick, Tais Hanae; Santos, Danúbia Silva dos; Mesquita, Fernanda Cristina Paccola; Vasques, Juliana Ferreira; Gubert, Fernanda; Rebelatto, Carmen Lúcia Kuniyoshi; Senegaglia, Alexandra Cristina; Brofman, Paulo Roberto Slud

    Abstract in English:

    Abstract Induced pluripotent stem cells (iPSCs) are generated from adult cells that have been reprogrammed to pluripotency. However, in vitro cultivation and genetic reprogramming increase genetic instability, which could result in chromosomal abnormalities. Maintenance of genetic stability after reprogramming is required for possible experimental and clinical applications. The aim of this study was to analyze chromosomal alterations by using the G-banding karyotyping method applied to 97 samples from 38 iPSC cell lines generated from peripheral blood or Wharton’s jelly. Samples from patients with long QT syndrome, Jervell and Lange-Nielsen syndrome and amyotrophic lateral sclerosis and from normal individuals revealed the following chromosomal alterations: acentric fragments, chromosomal fusions, premature centromere divisions, double minutes, radial figures, ring chromosomes, polyploidies, inversions and trisomies. An analysis of two samples generated from Wharton’s jelly before and after reprogramming showed that abnormal clones can emerge or be selected and generate an altered lineage. IPSC lines may show clonal and nonclonal chromosomal aberrations in several passages (from P6 to P34), but these aberrations are more common in later passages. Many important chromosomal aberrations were detected, showing that G-banding is very useful for evaluating genetic instability with important repercussions for the application of iPSC lines.
  • Expression of methyl farnesoate epoxidase (mfe) and juvenile hormone esterase (jhe) genes and their relation to social organization in the stingless bee Melipona interrupta (Hymenoptera: Apidae) Animal Genetics

    Brito, Diana Vieira; Silva, Carlos Gustavo Nunes da; Rêgo, Livia Cristina Neves; Carvalho-Zilse, Gislene Almeida

    Abstract in English:

    Abstract Social organization in highly eusocial bees relies upon two important processes: caste differentiation in female larvae, and age polyethism in adult workers. Juvenile Hormone (JH) is a key regulator of both processes. Here we investigated the expression of two genes involved in JH metabolism - mfe (biosynthesis) and jhe (degradation) - in the context of social organization in the stingless bee Melipona interrupta. We found evidence that the expression of mfe and jhe genes is related to changes in JH levels during late larval development, where caste determination occurs. Also, both mfe and jhe were upregulated when workers engage in intranidal tasks, but only jhe expression was downregulated at the transition from nursing to foraging activities. This relation is different than expected, considering recent reports of lower JH levels in foragers than nurses in the closely related species Melipona scutellaris. Our findings suggest that highly eusocial bees have different mechanisms to regulate JH and, thus, to maintain their level of social organization.
  • Multiple haplotypes of Chelonia mydas juveniles in a threatened hotspot area in Southern Brazil Animal Genetics

    Savada, Camila Satie; Prosdocimi, Laura; Domit, Camila; Almeida, Fernanda Simões de

    Abstract in English:

    Abstract Mixed stocks are described for Chelonia mydas and the frequency of haplotypes in feeding areas can aid understanding of the genetic and ecological diversity, since with this information it is possible to identify the origin of the individuals. The current study aims to characterize and compare genetic diversity along the coast of Paraná with 17 other feeding areas in the Atlantic Ocean. A total of 285 samples from juveniles were DNA sequenced in the control region, resulting in the identification of 12 haplotypes, with a predominance of the CMA8 haplotype (69%) and the first registration of CMA23. For the study subjects, haplotypic and nucleotide diversity were 0.469 ± 0.032 and 0.00189 ± 0.00020, respectively, and comparisons with other feeding areas presented significant values for the majority of FST and ΦST. The results point to the importance of this region and provide evidence that over the years a mixed stock has used the region as a feeding area. This variation could be related to sea currents, climatic changes, and oceanographic characteristics that may alter the availability of food, water temperature, and the presence of turtles. The current results can be considered in conservation plans for Chelonia mydas.
  • Meiotic self-pairing of the Psalidodon (Characiformes, Characidae) iso-B chromosome: A successful perpetuation mechanism Animal Genetics

    Silva, Duílio Mazzoni Zerbinato de Andrade; Araya-Jaime, Cristian; Yamashita, Masakane; Vidal, Mateus Rossetto; Oliveira, Claudio; Porto-Foresti, Fábio; Artoni, Roberto Ferreira; Foresti, Fausto

    Abstract in English:

    Abstract B chromosomes are non-essential additional genomic elements present in several animal and plant species. In fishes, species of the genus Psalidodon (Characiformes, Characidae) harbor great karyotype diversity, and multiple populations carry different types of non-essential B chromosomes. This study analyzed how the dispensable supernumerary B chromosome of Psalidodon paranae behaves during meiosis to overcome checkpoints and express its own meiosis-specific genes. We visualized the synaptonemal complexes of P. paranae individuals with zero, one, or two B chromosomes using immunodetection with anti-medaka SYCP3 antibody and fluorescence in situ hybridization with a (CA)15 microsatellite probe. Our results showed that B chromosomes self-pair in cells containing only one B chromosome. In cells with two identical B chromosomes, these elements remain as separate synaptonemal complexes or close self-paired elements in the nucleus territory. Overall, we reveal that B chromosomes can escape meiotic silencing of unsynapsed chromatin through a self-pairing process, allowing expression of their own genes to facilitate regular meiosis resulting in fertile individuals. This behavior, also seen in other congeneric species, might be related to their maintenance throughout the evolutionary history of Psalidodon.
  • The complete plastid genome of Cotinus coggygria and phylogenetic analysis of the Anacardiaceae Plant Genetics

    Xu, Lingfeng; Zhou, Nong; Zhao, Shunxin; Li, Jingling; Pei, Xiaoying; Yu, Jie; Guo, Dongqin

    Abstract in English:

    Abstract Cotinus coggygria Scop. (Anacardiaceae) is an important ornamental tree with beautiful characteristics that is grown in China. In this study, the complete plastid genome of C. coggygria was sequenced and assembled. This genome was 158,843 bp in size and presented a typical tetrad structure, consisting of a large single-copy region (87,121 bp), a pair of inverted repeat regions (26,829 bp), and a small single-copy region (18,064 bp). A total of 134 genes were annotated, including 88 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. We observed a deletion that caused the loss of the rpl32 gene, and a small expansion of IR regions resulted in the trnH gene accessing IR regions; two copies were obtained. Phylogenetic analysis showed that C. coggygria was most closely related to Pistacia, with 100% bootstrap support within Anacardiaceae. In this study, we report the plastid genome of Cotinus species for the first time, which provides insight into the evolution of the plastid genome in Anacardiaceae and promotes the understanding of Cotinus plants.
  • Orf165 is associated with cytoplasmic male sterility in pepper Plant Genetics

    Wen, Jin-fen; Zhao, Kai; Lv, Jun-heng; Huo, Jin-long; Wang, Zi-ran; Wan, Hong-jian; Zhu, Hai-shan; Zhang, Zhu-qing; Shao, Gui-fang; Wang, Jiao; Zhang, Shui; Yang, Ting-yu; Zhang, Jing-rou; Zou, Xue-xiao; Deng, Ming-hua

    Abstract in English:

    Abstract Cytoplasmic male sterility (CMS) is a maternally inherited trait that derives from the inability to produce functional pollen in higher plants. CMS results from recombination of the mitochondrial genome. However, understanding of the molecular mechanism of CMS in pepper is limited. In this study, comparative transcriptomic analyses were performed using a near-isogenic CMS line 14A (CMS-14A) and a maintainer line 14B (ML-14B) as experimental materials. A total of 17,349 differentially expressed genes were detected between CMS-14A and ML-14B at the PMC meiosis stage. Among them, six unigenes associated with CMS and 108 unigenes involved in energy metabolism were identified. The gene orf165 was found in CMS-14A. When orf165 was introduced into ML-14B, almost 30% of transgenic plants were CMS. In addition, orf165 expression in transgenic CMS plants resulted in abnormal function of some genes involved in energy metabolism. When orf165 in transgenic CMS plant was silenced, the resulted orf165-silenced plant was male fertile and the expression patterns of some genes associated with energy metabolism were similar to ML-14B. Thus, we confirmed that orf165 influenced CMS in pepper.
  • Genome-wide analysis of the maize superoxide dismutase (SOD) gene family reveals important roles in drought and salt responses Plant Genetics

    Liu, Jing; Xu, Lijuan; Shang, Jian; Hu, Xiaolin; Yu, Haitao; Wu, Hongying; Lv, Wenben; Zhao, Yang

    Abstract in English:

    Abstract Superoxide dismutase proteins (SODs) are antioxidant enzymes with important roles in abiotic stress responses. The SOD gene family has been systematically analyzed in many plants; however, it is still poorly understood in maize. Here, a bioinformatics analysis of maize SOD gene family was conducted by describing gene structure, conserved motifs, phylogenetic relationships, gene duplications, promoter cis-elements and GO annotations. In total, 13 SOD genes were identified in maize and five members were involved in segmental duplication. Phylogenetic analysis indicated that SODs from maize and other plants comprised two groups, which could be further classified into different subgroups, with most members in the same subgroup having the same subcellular localization. The ZmSOD promoters contained 2-10 stress-responsive cis-elements with different distributions. Heatmap analysis indicated that ZmSODs were expressed in most of the detected tissues and organs. The expression patterns of ZmSODs were investigated under drought and salt treatments by qRT-PCR, and most members were responsive to drought or salt stress, especially some ZmSODs with significant expression changes were identified, such as ZmCSD2 and ZmMSD2, suggesting the important roles of ZmSODs in abiotic stress responses. Our results provide an important basis for further functional study of ZmSODs in future study.
  • Transcriptome sequencing and screening of genes related to glucose availability in Schizosaccharomyces pombe by RNA-seq analysis Genetics of Microorganisms

    Tarhan, Çağatay; Çakır, Özgür

    Abstract in English:

    Abstract While calorie restriction is the most used experimental intervention to increase lifespan in numerous model organisms, increasing evidence suggests that excess glucose leads to decreased lifespan in various organisms. To fully understand the molecular basis of the pro-aging effect of glucose, it is still important to discover genetic interactions, gene expression patterns, and molecular responses depending on glucose availability. Here, we compared the gene expression profiles in Schizosaccharomyces pombe mid-log-phase cells grown in three different Synthetic Dextrose media with 3%, 5%, and 8% glucose, using the RNA sequencing method. Expression patterns of genes that function in carbohydrate metabolism were downregulated as expected, and these genes were downregulated in line with the increase in glucose content. Significant and consistent changes in the expression were observed such as genes that encoding retrotransposable elements, heat shock proteins, glutathione S-transferase, cell agglutination protein, and conserved fungal proteins. We group some genes that function together in the transcription process and mitotic regulation, which have recently been associated with glucose availability. Our results shed light on the relationship between excess glucose, diverse cellular processes, and aging.
  • An efficient Agrobacterium tumefaciens-mediated transformation method for Simplicillium subtropicum (Hypocreales: Cordycipitaceae) Genetics of Microorganisms

    Sbaraini, Nicolau; Tomazett, Mariana Vieira; Penteriche, Augusto Bartz; Gonçales, Relber Aguiar; Camargo, Matheus da Silva; Bailão, Alexandre Melo; Borges, Clayton Luiz; Schrank, Augusto; Soares, Célia Maria de Almeida; Staats, Charley Christian

    Abstract in English:

    Abstract Filamentous fungi are the organisms of choice for most industrial biotechnology. Some species can produce a variety of secondary metabolites and enzymes of commercial interest, and the production of valuable molecules has been enhanced through different molecular tools. Methods for genetic manipulation and transformation have been essential for the optimization of these organisms. The genus Simplicillium has attracted increased attention given several potential biotechnological applications. The Simplicillium genus harbors several entomopathogenic species and some isolates have been explored for bioremediation of heavy metal contaminants. Furthermore, the myriad of secondary metabolites isolated from Simplicillium spp. render these organisms as ideal targets for deep exploration and further biotechnological mining possibilities. However, the lack of molecular tools hampered the exploration of this genus. Thus, an Agrobacterium tumefaciens-mediated transformation method was established for Simplicillium subtropicum, employing the far-red fluorescent protein TURBOFP635/Katushka, as a visual marker, and the selection marker SUR gene, that confers resistance to chlorimuron ethyl. Notably, one round of transformation using the established method yielded almost 400 chlorimuron resistant isolates. Furthermore, these transformants displayed mitotic stability for, at least, five generations. We anticipate that this method can be useful for deep molecular exploration and improvement of strains in the Simplicillium genus.
  • Cis-trimethoxystilbene, exhibits higher genotoxic and antiproliferative effects than its isomer trans-trimethoxystilbene in MCF-7 and MCF-10A cell lines Mutagenesis

    Gonçalves, Natália dos Santos; Mello, Tamires Maria Silva Pereira de; Mizuno, Cássia Suemi; Haider, Saqlain; Santos, Raquel Alves dos

    Abstract in English:

    Abstract Stilbenes are a class of natural compounds with a wide variety of biological effects, such as antitumor activity. The best-known stilbene is resveratrol, whose clinical application is limited due to its low bioavailability. Methoxylated derivatives of this stilbene, including cis-trimethoxystilbene (cis-TMS) and trans-trimethoxystilbene (trans-TMS) have demonstrated more pronounced cytotoxic and anti-proliferative effects than resveratrol. Thus, the objective of this study is to evaluate and compare the cytotoxicity and antiproliferative effects of cis- and trans-TMS in MCF-7 and its normal counterpart MCF-10A. Both compounds were cytotoxic, genotoxic, and induced G2-M accumulation and cell death in the two cell lines. These results suggested that the genotoxicity of cis- and trans-TMS is involved in the reduction of cellular proliferation of MCF-7 and MCF-10A cells, but notably, such antiproliferative effects are more pronounced for cis- than trans-TMS.
  • FOXE1 polymorphisms and chronic exposure to nitrates in drinking water cause metabolic dysfunction, thyroid abnormalities, and genotoxic damage in women Mutagenesis

    Gandarilla-Esparza, Diana Dennys; Calleros-Rincón, Esperanza Yasmin; Macias, Hortensia Moreno; González-Delgado, María Fernanda; Vargas, Gonzalo García; Sustaita, Jaime Duarte; González-Zamora, Alberto; Ríos-Sánchez, Efraín; Pérez-Morales, Rebeca

    Abstract in English:

    Abstract Nitrates in drinking water has been associated to adverse health effects, including changes in glucose and lipid levels, thyroid hormone imbalance and adverse reproductive effects. We analyzed metabolic and thyroid hormone alterations and genotoxic damage in women with chronic exposure to nitrates in drinking water. The concentration of nitrates in drinking water was quantified and according to this parameter, participants were divided into three exposure scenarios. Blood and urine samples were collected from 420 women living in Durango, Mexico and biomarkers were determined. We found nitrates concentrations in drinking water above the permissible limit (>50 mg/L), and an increase in the percentage of methemoglobin (p=0.0001), nitrite in blood plasma and urine (p=0.0001), glucose (p=0.0001), total cholesterol (p=0.001), LDL (p=0.001) and triglycerides (p=0.0001). We also found alterations in TSH (p=0.01), fT3 (p=0.0003), T4T (p=0.01) and fT4 (p=0.0004) hormones. Frequency of subclinical hypothyroidism was 8.33%; differences in FOXE1 (rs965513, rs1867277) genotypes distribution were found and both polymorphisms were associated with a decrease in TSH. A high percentage of micronucleus in binucleate lymphocyte cells was found (35%, p=0.0001). In conclusion, the chronic exposure to nitrates in water for human consumption caused metabolic and hormonal alterations and genotoxic damage in women.
  • Cryptic diversity and diversification processes in three cis-Andean Rhamdia species (Siluriformes: Heptapteridae) revealed by DNA barcoding Evolutionary Genetics

    Ribolli, Josiane; Zaniboni Filho, Evoy; Scaranto, Bianca Maria Soares; Shibatta, Oscar Akio; Machado, Carolina Barros

    Abstract in English:

    Abstract The wide distribution of the Neotropical freshwater catfish Rhamdia offers an excellent opportunity to investigate the historical processes responsible for modeling South America’s hydrogeological structure. We used sequences from cis-Andean and Mesoamerican Rhamdia species to reconstruct and estimate divergence times among cis-Andean lineages, correlating the results with known geological events. Species delimitation methods based on distance (DNA barcoding and BIN) and coalescence (GMYC) approaches identified nine well-supported lineages from the cis-Andean region from sequences available in the BOLD dataset. The cis-Andean Rhamdia lineages diversification process began in Eocene and represented the split between cis-Andean and Mesoamerican clades. The cis-Andean clade contains two principal groups: Northwest clade (MOTUs from Amazon, Essequibo, Paraguay, and Itapecuru basins) and Southeast clade (Eastern Brazilian shield basins (Paraná, Uruguay, Iguaçu, and São Francisco) plus eastern coastal basins). The diversification of the cis-Andean Rhamdia lineages results from vicariance and geodispersion events, which played a key role in the current intricate distribution pattern of the Rhamdia lineages. The wide geographical distribution and large size of the specimens make it attractive to cultivate in different countries of the Neotropical region. The lineages delimitation minimizes identification mistakes, unintentional crossings by aquaculture, and reduces natural stocks contamination.
  • Evolution of sex-ratio: Brief review with mathematical study of some simple novel models Evolutionary Genetics

    Otto, Paulo A.

    Abstract in English:

    Abstract Besides reviewing the unusual case of sex-ratio in the lemming and presenting alternative analyses of general models in which the shift in the usual sex-ratio 1:1 is determined by autosomal or sex-linked mutant alleles, three novel models are presented, in which the shift on the progeny sex-ratio depends on the number of copies of a mutant allele present in the parental pair. The analysis of these models with additive effects shows that: 1) autosomal mutations that alter the usual sex-ratio are eliminated from the population; 2) mutations occurring on the X chromosome lead to an evolutionary stable 1:1 sex-ratio only if the mutation favors the production of males; when the mutant allele favors the production of females, however, females will prevail in the population, with a frequency dependent impact on δ (the deviation from the usual 0.5 proportion) ; for most of the range of possible values of δ the stable but extraordinary sex-ratio will vary from 1 male : 1 female to 1 male : 3 females or 1 male : 2 females approximately depending whether the mutant allele is randomly inactivated or not.
  • Mitogenome of Coprophanaeus ensifer and phylogenetic analysis of the Scarabaeidae family (Coleoptera) Evolutionary Genetics

    Mello, Catarine Aragone de Albuquerque; Amorim, Igor Costa; Silva, Alexandre Freitas da; Medeiros, Giuliene Rocha de; Wallau, Gabriel Luz; Moura, Rita de Cássia de

    Abstract in English:

    Abstract Several studies about the phylogenetic relationships of the Scarabaeinae subfamily (Coleoptera: Scarabaeidae) have been performed, but some phylogenetic uncertainties persist including the relationship and monophyly of different tribes and some genera. The aim of this study was to characterize the mitogenome of Coprophanaeus ensifer in order to establish its position within the Scarabaeidae family and to contribute to the resolution of some phylogenetic uncertainties. The mitogenome was sequenced on the Illumina HiSeq 4000, assembled using the Mitobim software and annotated in MITOS WebServer. The phylogenetic trees were reconstructed by Bayesian inference. The C. ensifer mitogenome is a molecule of 14,964 bp that contains the number and organization of the genes similar to those of most Coleoptera species. Phylogenetic reconstruction suggests monophyly of the tribe Phanaeini and supports the hypothesis that Coprini is a sister group of Phanaeini. The results also revealed the position of the tribe Oniticellini which is grouped with Onthophagini and Onitini. The geographic distribution of these species that form the most ancestral clade suggests with Scarabaeinae originated in Africa.
  • Resveratrol prevents inflammation and oxidative stress response in LPS-induced human gingival fibroblasts by targeting the PI3K/AKT and Wnt/β-catenin signaling pathways Cellular, Molecular and Developmental Genetics

    Li, Lihua; Li, Junxiong; Wang, Yujiao; Liu, Xin; Li, Siyu; Wu, Yan; Tang, Wanrong; Qiu, Ya

    Abstract in English:

    Abstract This study aimed to elucidate the anti-inflammatory and antioxidant properties of resveratrol (RSV) in human gingival fibroblasts (HGFs) following stimulation by P. gingivalis lipopolysaccharide (LPS). The levels of the inflammatory cytokines IL-1β, IL-6, IL-8 and TNFα, the activity of the antioxidant enzymes SOD and GSH-Px, and the levels of MDA, were evaluated by ELISA. It was observed that the expression of IL-1β, IL-6, IL-8 and TNFα in LPS-induced HGFs was significantly downregulated by RSV in a dose-dependent manner. RSV also partly increased oxidative stress (OS)-related factors, including SOD and GSH-Px, which was accompanied by a decrease in MDA production, although the results were not statistically significant. Additionally, RSV-induced deactivation of the PI3K/AKT and Wnt/β-catenin pathways in LPS-induced HGFs was observed by western blot analysis. Subsequently, it was demonstrated treatment with PI3K/AKT pathway inhibitor (LY294002) or Wnt/β-catenin pathway inhibitor (Dickkopf-1, DKK-1) could further enhance the anti-inflammatory and antioxidant effects of RSV by downregulating the expression of IL-1β, IL-6, IL-8 and TNFα, and the production of MDA, and increasing the activity of SOD and GSH-Px in LPS-induced HGFs. These results suggested RSV attenuated the inflammation and OS injury of P. gingivalis LPS-treated HGFs by deactivating the PI3K/AKT and Wnt/β-catenin signaling pathways.
  • Transcriptomic analysis reveals that mTOR pathway can be modulated in macrophage cells by the presence of cryptococcal cells Cellular, Molecular and Developmental Genetics

    Piffer, Alícia C.; Santos, Francine M. dos; Thomé, Marcos P.; Diehl, Camila; Garcia, Ane Wichine Acosta; Kinskovski, Uriel Perin; Schneider, Rafael de Oliveira; Gerber, Alexandra; Feltes, Bruno César; Schrank, Augusto; Vasconcelos, Ana Tereza R.; Lenz, Guido; Kmetzsch, Lívia; Vainstein, Marilene H.; Staats, Charley C.

    Abstract in English:

    Abstract Cryptococcus neoformans and Cryptococcus gattii are the etiological agents of cryptococcosis, a high mortality disease. The development of such disease depends on the interaction of fungal cells with macrophages, in which they can reside and replicate. In order to dissect the molecular mechanisms by which cryptococcal cells modulate the activity of macrophages, a genome-scale comparative analysis of transcriptional changes in macrophages exposed to Cryptococcus spp. was conducted. Altered expression of nearly 40 genes was detected in macrophages exposed to cryptococcal cells. The major processes were associated with the mTOR pathway, whose associated genes exhibited decreased expression in macrophages incubated with cryptococcal cells. Phosphorylation of p70S6K and GSK-3β was also decreased in macrophages incubated with fungal cells. In this way, Cryptococci presence could drive the modulation of mTOR pathway in macrophages possibly to increase the survival of the pathogen.
  • EphA2 overexpression reduces H2O2-induced damage of lens epithelial cells Cellular, Molecular and Developmental Genetics

    Ji, Qingshan; Liu, Jing; Wang, Guifang; Liu, Lian; Zhong, Jingxiang

    Abstract in English:

    Abstract Age-related cataract (ARC) is a progressive lens opacification that occurs from middle to old age. Eph-receptor tyrosinekinase-type A2 (EphA2) has been reported to be associated with ARC. This work aims to investigate the molecular mechanism of EphA2 in ARC. We treated human lens epithelial cells (SRA01/04) with different concentration of H2O2 to induce lens epithelial cell damage. Then, we found that H2O2 treatment significantly suppressed cell viability and enhanced the expression of EphA2 in the SRA01/04 cells. H2O2 treatment repressed cell viability and enhanced the levels of reactive oxygen species (ROS) in SRA01/04 cells, which was partly abolished by EphA2 up-regulation. Moreover, EphA2 overexpression reduced H2O2-induced apoptosis of SRA01/04 cells. EphA2 up-regulation caused an up-regulation of Bcl-2, and repressed the expression of Bax and Cleaved-caspase-3 in the SRA01/04 cells following H2O2 treatment. In conclusion, our data confirm that EphA2 overexpression enhances cell viability and inhibits apoptosis in the H2O2-treated SRA01/04 cells, thereby reducing H2O2-induced damage of lens epithelial cells. Thus, this work provides new insights into the mechanism of EphA2 in ARC.
  • Periostin regulates osteogenesis of mesenchymal stem cells from ovariectomized rats through actions on the ILK/Akt/GSK-3β Axis Cellular, Molecular and Developmental Genetics

    Liu, Silin; Jin, Zuolin; Cao, Meng; Hao, Dandan; Li, Chunrong; Li, Doudou; Zhou, Weiwei

    Abstract in English:

    Abstract Osteoporosis is a condition of the skeleton that mainly results from estrogen deficiency. Periostin is a matricellular component in bone that is involved in osteoblast differentiation. However, how Periostin promotes osteogenesis remains largely unknown. Here, we isolated bone marrow skeletal stem cells (BMSCs) derived from an ovariectomy (OVX)-induced osteoporosis rat model and the effects of periostin on BMSCs derived from OVX rats (OVX-BMSCs) were assessed. Overexpression of periostin enhanced alkaline phosphatase (ALP) and alizarin red staining in OVX-BMSCs as well as the osteogenic genes OCN, BSP and Runx2. ILK is a downstream effector of signals from the extracellular matrix and participates in bone homeostasis. Overexpression of periostin also increased expression of protein levels for ILK, as well as the downstream targets pAkt and pGSK3β. Suppression of ILK or Akt partially suppressed the enhancement of osteogenic ability induced by periostin overexpression in OVX-BMSCs. Thus, periostin may promote the osteogenic ability of OVX-BMSCs through actions on the ILK/Akt/GSK3β axis.
  • An integrated approach to identify bimodal genes associated with prognosis in câncer Genomics and Bioinformatics

    Justino, Josivan Ribeiro; Reis, Clovis Ferreira dos; Fonseca, Andre Luis; Souza, Sandro Jose de; Stransky, Beatriz

    Abstract in English:

    Abstract Bimodal gene expression (where a gene expression distribution has two maxima) is associated with phenotypic diversity in different biological systems. A critical issue, thus, is the integration of expression and phenotype data to identify genuine associations. Here, we developed tools that allow both: i) the identification of genes with bimodal gene expression and ii) their association with prognosis in cancer patients from The Cancer Genome Atlas (TCGA). Bimodality was observed for 554 genes in expression data from 25 tumor types. Furthermore, 96 of these genes presented different prognosis when patients belonging to the two expression peaks were compared. The software to execute the method and the corresponding documentation are available at the Data access section.
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