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Genetics and Molecular Biology, Volume: 47, Número: 2, Publicado: 2024
  • LTBP2 regulates cisplatin resistance in GC cells via activation of the NF-κB2/BCL3 pathway Human And Medical Genetics

    Wang, Jun; Liang, Wenjia; Wang, Xiangwen; Chen, Zhao; Jiang, Lei

    Resumo em Inglês:

    Abstract Gastric cancer (GC) often develops resistance to cisplatin treatment, but while latent transforming growth factor β-binding protein (LTBP2) is recognized as a potential regulator in GC, its specific role in cisplatin resistance is not fully understood. This study investigated LTBP2’s impact on cisplatin resistance in GC. LTBP2 expression was assessed in various GC cell lines, and its correlation with cisplatin sensitivity was determined through cell viability assays. Lentivirus-mediated LTBP2 silencing in HGC-27 cells demonstrated enhanced cisplatin sensitivity, reduced cell proliferation, and inhibition of the NF-κB2/Bcl-3/cyclin D1 pathway. Additionally, transient transfection overexpressed the NFκB2 gene in LTBP2-silenced HGC-27/DDPR cells, restoring cisplatin sensitivity and upregulating p52/Bcl-3/cyclin D1. In conclusion, silencing LTBP2 could effectively inhibit cell proliferation and mitigate cisplatin resistance via the NFKB noncanonical pathway NFKB2 p52/Bcl-3/cyclin D1. These findings propose LTBP2 as a potential therapeutic target for overcoming cisplatin resistance in GC patients.
  • GJB2 c.35del variant up-regulates GJA1 gene expression and affects differentiation of human stem cells Human And Medical Genetics

    Batissoco, Ana Carla; Cruz, Dayane Bernardino; Alegria, Thiago Geronimo Pires; Kobayashi, Gerson; Oiticica, Jeanne; Soares Netto, Luis Eduardo; Passos-Bueno, Maria Rita; Haddad, Luciana Amaral; Mingroni Netto, Regina Célia

    Resumo em Inglês:

    Abstract Pathogenic DNA alterations in GJB2 are present in nearly half of non-syndromic hearing loss cases with autosomal recessive inheritance. The most frequent variant in GJB2 causing non-syndromic hearing loss is the frameshifting c.35del. GJB2 encodes Cx26, a protein of the connexin family that assembles hemichannels and gap junctions. The expression of paralogous proteins is believed to compensate for the loss of function of specific connexins. As Cx26 has been involved in cell differentiation in distinct tissues, we employed stem cells derived from human exfoliated deciduous teeth (SHEDs), homozygous for the c.35del variant, to assess GJB2 roles in stem cell differentiation and the relationship between its loss of function and the expression of paralogous genes. Primary SHED cultures from patients and control individuals were compared. SHEDs from patients had significantly less GJB2 mRNA and increased amount of GJA1 (Cx43), but not GJB6 (Cx30) or GJB3 (Cx31) mRNA. In addition, they presented higher induced differentiation to adipocytes and osteocytes but lower chondrocyte differentiation. Our results suggest that GJA1 increased expression may be involved in functional compensation for GJB2 loss of function in human stem cells, and it may explain changes in differentiation properties observed in SHEDs with and without the c.35del variant.
  • Putative protective genomic variation in the Lithuanian population Human And Medical Genetics

    Žukauskaitė, Gabrielė; Domarkienė, Ingrida; Rančelis, Tautvydas; Kavaliauskienė, Ingrida; Baronas, Karolis; Kučinskas, Vaidutis; Ambrozaitytė, Laima

    Resumo em Inglês:

    Abstract Genomic effect variants associated with survival and protection against complex diseases vary between populations due to microevolutionary processes. The aim of this study was to analyse diversity and distribution of effect variants in a context of potential positive selection. In total, 475 individuals of Lithuanian origin were genotyped using high-throughput scanning and/or sequencing technologies. Allele frequency analysis for the pre-selected effect variants was performed using the catalogue of single nucleotide polymorphisms. Comparison of the pre-selected effect variants with variants in primate species was carried out to ascertain which allele was derived and potentially of protective nature. Recent positive selection analysis was performed to verify this protective effect. Four variants having significantly different frequencies compared to European populations were identified while two other variants reached borderline significance. Effect variant in SLC30A8 gene may potentially protect against type 2 diabetes. The existing paradox of high rates of type 2 diabetes in the Lithuanian population and the relatively high frequencies of potentially protective genome variants against it indicate a lack of knowledge about the interactions between environmental factors, regulatory regions, and other genome variation. Identification of effect variants is a step towards better understanding of the microevolutionary processes, etiopathogenetic mechanisms, and personalised medicine.
  • ΔNp63α promotes cigarette smoke-induced renal cancer stem cell activity via the Sonic Hedgehog pathway Human And Medical Genetics

    Zhao, Yuxiang; Ma, Nannan; Wu, Wanngyu; Wu, Ying; Zhang, Wenbo; Qian, Weiwei; Sun, Xin; Zhang, Tao

    Resumo em Inglês:

    Abstract Cigarette smoke (CS) has been generally recognized as a chief carcinogenic factor in renal cell carcinoma (RCC). The stimulative effect of CS on renal cancer stem cells (RCSCs) has been described previously. The Sonic Hedgehog (SHH) pathway plays an essential role in self-renewal, cell growth, drug resistance, metastasis, and recurrence of cancer stem cells (CSCs). Renal cancer-related gene ΔNp63α is highly expressed in renal epithelial tissues and contributes to the RCSCs characteristics of tumors. The aim of this study was to elucidate the role of ΔNp63α and the SHH pathway on the activity of RCSCs induced by CS through a series of in vivo and in vitro studies. It was shown that in renal cancer tissues, ΔNp63α and RCSCs markers in smokers are expressed higher than that in non-smokers. RCSCs were effectively enriched by tumor sphere formation assay. Besides, CS increased the expression of RCSCs markers and the capability of sphere-forming in vitro and in vivo. Moreover, the SHH pathway was activated, and the specialized inhibitor alleviated the promotion of CS on RCSCs. ΔNp63α activated the SHH pathway and promoted CS-induced enhancement of RCSCs activity. These findings indicate that ΔNp63α positively regulates the activity of CS-induced RCSCs via the SHH pathway.
  • Characterization of the chemoreceptor repertoire of a highly specialized fly with comparisons to other Drosophila species Animal Genetics

    Fonseca, Pedro Mesquita; Robe, Lizandra Jaqueline; Carvalho, Tuane Letícia; Loreto, Elgion Lucio Silva

    Resumo em Inglês:

    Abstract To explore the diversity of scenarios in nature, animals have evolved tools to interact with different environmental conditions. Chemoreceptors are an important interface component and among them, olfactory receptors (ORs) and gustatory receptors (GRs) can be used to find food and detect healthy resources. Drosophila is a model organism in many scientific fields, in part due to the diversity of species and niches they occupy. The contrast between generalists and specialists Drosophila species provides an important model for studying the evolution of chemoreception. Here, we compare the repertoire of chemoreceptors of different species of Drosophila with that of D. incompta, a highly specialized species whose ecology is restricted to Cestrum flowers, after reporting the preferences of D. incompta to the odor of Cestrum flowers in olfactory tests. We found evidence that the chemoreceptor repertoire in D. incompta is smaller than that presented by species in the Sophophora subgenus. Similar patterns were found in other non-Sophophora species, suggesting the presence of underlying phylogenetic trends. Nevertheless, we also found autapomorphic gene losses and detected some genes that appear to be under positive selection in D. incompta, suggesting that the specific lifestyle of these flies may have shaped the evolution of individual genes in each of these gene families.
  • Partial molecular characterization, expression pattern and polymorphism analysis of MHC I genes in Chinese domestic goose (Anser cygnoides) Animal Genetics

    Zeng, Qianqian; Li, Xiaojie; Shi, Xiaomin; Yan, Shigan

    Resumo em Inglês:

    Abstract Major histocompatibility complex (MHC) allelic polymorphism is critically important for mediating antigen presentation in vertebrates. Presently, there are insufficient studies of MHC genetic diversity in domestic Anseriform birds. In this study, we analyzed the expression profile of MHC I genes and screened for MHC I exon 2 polymorphism in one domestic goose population from China using Illumina MiSeq sequencing. The results showed that four MHC I alleles (Ancy-IE2*09/*11/*13/*21) in one goose were identified based on cDNA cloning and sequencing using four primer combinations, and the varying number of cDNA clones implied that these four classical sequences showed differential expression patterns. Through next-generation sequencing, 27 alleles were obtained from 68 geese with 3-10 putative alleles per individual, indicating at least the existence of 5 MHC I loci in the goose. The marked excess of the non-synonymous over the synonymous substitution in the peptide-binding region (PBR) along 27 alleles and five positively selected sites (PSSs) detected around the PBR indicated that balancing selection might be the major force in shaping high MHC variation in the goose. Additionally, IA alleles displaying lower polymorphism were subject to less positive selection pressure than non-IA alleles with a higher level of polymorphism.
  • The complete chloroplast genome of Dicliptera tinctoria (Nees) Kostel. and comparative analysis of chloroplast genomes in Acanthaceae Plant Genetics

    Le, Thi Thanh Nga; Vu, Minh Thiet; Do, Hoang Dang Khoa

    Resumo em Inglês:

    Abstract Dicliptera tinctoria is a member of Acanthaceae, which has a wide distribution and contains potentially medicinal species, and exhibited pharmaceutical potentials. This study sequenced and characterized the complete chloroplast genome of Dicliptera tinctoria. The newly sequenced cpDNA of D. tinctoria was 150,733 bp in length and had a typical quadripartite structure consisting of a large single copy (LSC, 82,895 bp), a small single copy (SSC, 17,249 bp), and two inverted repeat (IRs, 25,295 bp each) regions. This genome also contained 80 protein-coding genes, 30 transfer RNAs, and four ribosomal RNAs, which is identical to other chloroplast genomes in Acanthaceae family. Nucleotides diversity analysis among chloroplast genomes of Acanthaceae species revealed eight hypervariable regions, including trnK_UUU-matK, trnC_GCA-petN, accD, rps12-clpP, rps3-rps19, ycf1-ndhF, ccsA-ndhD, and ycf1. Phylogenetic analysis revealed the paraphyly of Dicliptera species and monophyly in four Acanthaceae subfamilies. These results provide an overview of genomic variations in Acanthaceae chloroplast genome, which is helpful for further genomic studies.
  • The mitogenomic landscape of Banisteriopsis caapi (Malpighiaceae), the sacred liana used for ayahuasca preparation Plant Genetics

    Chavarro-Mesa, Edisson; Almeida, João Victor dos Anjos; Silva, Saura R.; Lopes, Simone Santos; Barbosa, Jose Beethoven Figueiredo; Oliveira, Danilo; Corrêa, Maria Alice; Moraes, Ana Paula; Miranda, Vitor F.O.; Prosdocimi, Francisco; Varani, Alessandro M.

    Resumo em Inglês:

    Abstract The sacred ayahuasca brew, utilized by indigenous communities in the Amazon and syncretic religious groups in Brazil, primarily consists of a decoction of two plants: (i) the Amazonian liana known as Mariri or Jagube (Banisteriopsis caapi), and (ii) the shrub referred as Chacrona or Rainha (Psychotria viridis). While Chacrona leaves are rich in N,N-Dimethyltryptamine (DMT), a potent psychedelic, the macerated vine of Mariri provides beta-carboline alkaloids acting as monoamine oxidase inhibitors, preventing DMT’s degradation. This study sequenced, assembled, and analyzed the complete genome of B. caapi’s mitochondrion, yielding a circular structure spanning 503,502 bp. Although the mtDNA encompasses most plant mitochondrial genes, it lacks some ribosomal genes, presents some atypical genes, and contains plastid pseudogenes, suggesting gene transfer between organelles. The presence of a 7-Kb repetitive segment containing copies of the rrnL and trnfM genes suggests mitogenome isomerization, supporting the hypothesis of dynamic mitogenome maintenance in plants. Phylogenetics and phylogenomics across 24 Malpighiales confirms the sample’s placement in the “Tucunacá” ethnovariety, aligning with morphological identification. This study spearheads efforts to decode the genome of this esteemed Malpighiaceae.
  • Revealing the role of Peg13: A promising therapeutic target for mitigating inflammation in sepsis Cellular, Molecular And Developmental Genetics

    Wang, dan; Lin, Zhiqiang; Su, Meixia; Zhou, Yiqing; Ma, Mengjie; Li, Minghui

    Resumo em Inglês:

    Abstract To investigate the role of Peg13 in modulating the inflammatory response in sepsis, we established Lipopolysaccharide (LPS)-induced 293T cells and mouse models. Peg13 expression was assessed at various time points after infection using RT-qPCR. The levels of high mobility group box 1 (HMGB1) and interleukin-6 (IL-6) were quantified through ELISA. A total of 44 septic patients and 36 healthy participants were recruited to measure Peg13 and HMGB1 levels in the blood. Peg13 demonstrated significant down-regulation in the supernatant of LPS-induced 293T cells and in the blood of LPS-induced mice. Moreover, the levels of proinflammatory cytokines HMGB1 and IL-6 were elevated in both the supernatant of LPS-induced cell models and blood specimens from LPS-induced murine models, and this elevation could be notably reduced by Peg13 suppression. In a clinical context, Peg13 and HMGB1 levels were higher in septic patients compared to healthy subjects. Peg13 exhibited a negative correlation with HMGB1, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) among septic patients. Peg13 mitigates the inflammatory response by reducing the release of proinflammatory cytokines HMGB1 and IL-6 in sepsis, presenting a potential therapeutic target for alleviating inflammation in sepsis treatment.
  • Expression profiling by high-throughput sequencing reveals GADD45, SMAD7, EGR-1 and HOXA3 activation in Myostatin (MSTN) and GDF11 treated myoblasts Cellular, Molecular And Developmental Genetics

    Braun, Platon; Alawi, Malik; Saygi, Ceren; Pantel, Klaus; Wagers, Amy J.

    Resumo em Inglês:

    Abstract Growth differentiation factor 11 (GDF11) and myostatin (MSTN/GDF8) are closely related members of the transforming growth factor β (TGFβ) superfamily, sharing structural homology. Despite these structural similarities, recent research has shed light on the distinct roles these ligands play within muscle tissue. This study aims to uncover both the differences and similarities in gene expression at the transcriptome level by utilizing RNA sequencing. We conducted experiments involving five distinct groups, each with three biological replicates, using C2C12 cell cultures. The cells were subjected to high-throughput profiling to investigate disparities in gene expression patterns following preconditioning with either GDF11 or MSTN at concentrations of 1 nM and 10 nM, respectively. In addition, control groups were established. Our research revealed concentration-dependent gene expression patterns, with 38 genes showing significant differences when compared to the control groups. Notably, GADD45, SMAD7, EGR-1, and HOXA3 exhibited significant differential expression. We also conducted an over-representation analysis, highlighting the activation of MAPK and JNK signaling pathways, along with GO-terms related to genes that negatively regulate metabolic processes, biosynthesis, and protein phosphorylation. This study unveiled the activation of several genes not previously discussed in existing literature whose full biological implications are yet to be determined in future research.
  • Investigating the shared genetic architecture between breast and ovarian cancers Genomics And Bioinformatics

    Shi, Xuezhong; Bu, Anqi; Yang, Yongli; Wang, Yuping; Zhao, Chenyu; Fan, Jingwen; Yang, Chaojun; Jia, Xiaocan

    Resumo em Inglês:

    Abstract High heritability and strong correlation have been observed in breast and ovarian cancers. However, their shared genetic architecture remained unclear. Linkage disequilibrium score regression (LDSC) and heritability estimation from summary statistics (ρ-HESS) were applied to estimate heritability and genetic correlations. Bivariate causal mixture model (MiXeR) was used to qualify the polygenic overlap. Then, stratified-LDSC (S-LDSC) was used to identify tissue and cell type specificity. Meanwhile, the adaptive association test called MTaSPUsSet was performed to identify potential pleiotropic genes. The Single Nucleotide Polymorphisms (SNP) heritability was 13% for breast cancer and 5% for ovarian cancer. There was a significant genetic correlation between breast and ovarian cancers (rg=0.21). Breast and ovarian cancers exhibited polygenic overlap, sharing 0.4 K out 2.8 K of causal variants. Tissue and cell type specificity displayed significant enrichment in female breast mammary, uterus, kidney tissues, and adipose cell. Moreover, the 74 potential pleiotropic genes were identified between breast and ovarian cancers, which were related to the regulation of cell cycle and cell death. We quantified the shared genetic architecture between breast and ovarian cancers and shed light on the biological basis of the co-morbidity. Ultimately, these findings facilitated the understanding of disease etiology.
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