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1.
Cell ; 185(1): 95-112.e18, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34995520

RESUMO

Fingerprints are of long-standing practical and cultural interest, but little is known about the mechanisms that underlie their variation. Using genome-wide scans in Han Chinese cohorts, we identified 18 loci associated with fingerprint type across the digits, including a genetic basis for the long-recognized "pattern-block" correlations among the middle three digits. In particular, we identified a variant near EVI1 that alters regulatory activity and established a role for EVI1 in dermatoglyph patterning in mice. Dynamic EVI1 expression during human development supports its role in shaping the limbs and digits, rather than influencing skin patterning directly. Trans-ethnic meta-analysis identified 43 fingerprint-associated loci, with nearby genes being strongly enriched for general limb development pathways. We also found that fingerprint patterns were genetically correlated with hand proportions. Taken together, these findings support the key role of limb development genes in influencing the outcome of fingerprint patterning.


Assuntos
Dermatoglifia , Dedos/crescimento & desenvolvimento , Organogênese/genética , Polimorfismo de Nucleotídeo Único , Dedos do Pé/crescimento & desenvolvimento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Povo Asiático/genética , Padronização Corporal/genética , Criança , Estudos de Coortes , Feminino , Membro Anterior/crescimento & desenvolvimento , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Proteína do Locus do Complexo MDS1 e EVI1/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
2.
Proc Natl Acad Sci U S A ; 120(24): e2216310120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276417

RESUMO

Many types of differentiated cells can reenter the cell cycle upon injury or stress. The underlying mechanisms are still poorly understood. Here, we investigated how quiescent cells are reactivated using a zebrafish model, in which a population of differentiated epithelial cells are reactivated under a physiological context. A robust and sustained increase in mitochondrial membrane potential was observed in the reactivated cells. Genetic and pharmacological perturbations show that elevated mitochondrial metabolism and ATP synthesis are critical for cell reactivation. Further analyses showed that elevated mitochondrial metabolism increases mitochondrial ROS levels, which induces Sgk1 expression in the mitochondria. Genetic deletion and inhibition of Sgk1 in zebrafish abolished epithelial cell reactivation. Similarly, ROS-dependent mitochondrial expression of SGK1 promotes S phase entry in human breast cancer cells. Mechanistically, SGK1 coordinates mitochondrial activity with ATP synthesis by phosphorylating F1Fo-ATP synthase. These findings suggest a conserved intramitochondrial signaling loop regulating epithelial cell renewal.


Assuntos
Mitocôndrias , Peixe-Zebra , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Células Epiteliais/metabolismo , Trifosfato de Adenosina/metabolismo
3.
J Chem Phys ; 160(14)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38591682

RESUMO

Designing homogeneous networks is considered one typical strategy for solving the problem of strength and toughness conflict of polymer network materials. Experimentalists have proposed the hypothesis of obtaining a structurally homogeneous hydrogel by crosslinking tetra-armed polymers, whose homogeneity was claimed to be verified by scattering characterization and other methods. Nevertheless, it is highly desirable to further evaluate this issue from other perspectives. In this study, a coarse-grained molecular dynamics simulation coupled with a stochastic reaction model is applied to reveal the topological structure of a polymer network synthesized by tetra-armed monomers as precursors. Two different scenarios, distinguished by whether internal cross-linking is allowed, are considered. We introduce the Dijkstra algorithm from graph theory to precisely characterize the network structure. The microscopic features of the network structure, e.g., loop size, dispersity, and size distribution, are obtained via the Dijkstra algorithm. By comparing the two reaction scenarios, Scenario II exhibits an overall more idealized structure. Our results demonstrate the feasibility of the Dijkstra algorithm for precisely characterizing the polymer network structure. We expect this work will provide a new insight for the evaluation and description of gel networks and further help to reveal the dynamic process of network formation.

4.
J Cell Sci ; 134(20)2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34545403

RESUMO

Compared with our extensive understanding of the cell cycle, we have limited knowledge of how the cell quiescence-proliferation decision is regulated. Using a zebrafish epithelial model, we report a novel signaling mechanism governing the cell quiescence-proliferation decision. Zebrafish Ca2+-transporting epithelial cells, or ionocytes, maintain high cytoplasmic Ca2+ concentration ([Ca2+]c) due to the expression of Trpv6. Genetic deletion or pharmacological inhibition of Trpv6, or reduction of external Ca2+ concentration, lowered the [Ca2+]c and reactivated these cells. The ionocyte reactivation was attenuated by chelating intracellular Ca2+ and inhibiting calmodulin (CaM), suggesting involvement of a Ca2+ and CaM-dependent mechanism. Long-term imaging studies showed that after an initial decrease, [Ca2+]c gradually returned to the basal levels. There was a concomitant decease in endoplasmic reticulum (ER) Ca2+ levels. Lowering the ER Ca2+ store content or inhibiting ryanodine receptors impaired ionocyte reactivation. Further analyses suggest that CaM-dependent protein kinase kinase (CaMKK) is a key molecular link between Ca2+ and Akt signaling. Genetic deletion or inhibition of CaMKK abolished cell reactivation, which could be rescued by expression of a constitutively active Akt. These results suggest that the quiescence-proliferation decision in zebrafish ionocytes is regulated by Trpv6-mediated Ca2+ and CaMKK-Akt signaling.


Assuntos
Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina , Proteínas Proto-Oncogênicas c-akt , Animais , Cálcio , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/genética , Peixe-Zebra/genética
5.
BMC Nephrol ; 24(1): 45, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849937

RESUMO

BACKGROUND: Accurate diagnosis and assessment of hematuria is crucial for the early detection of chronic kidney disease(CKD). As instability of urinary RBC count (URBC) often results with clinical uncertainty, therefore new urinary indexes are demanded to improve the accuracy of diagnosis of hematuria. In this study, we aimed to investigate the benefit of applying new complex indicators based on random urine red blood cell counts confirmed in hematuric kidney diseases. METHODS: All patients enrolled underwent renal biopsy, and their clinical information was collected. Urinary and blood biomedical indexes were implemented with red blood cell counts to derive complex indicators. Patients were divided into two groups (hematuria-dominant renal histologic lesions and non-hematuria-dominant renal histologic lesions) based on their renal pathological manifestations. The target index was determined by comparing the predictive capabilities of the candidate parameters for hematuric kidney diseases. Hematuria stratification was divided into four categories based on the scale of complex indicators and distributional features. The practicality of the new complex indicators was demonstrated by fitting candidate parameters to models comprising demographic information. RESULTS: A total of 1,066 cases (678 hematuria-dominant renal histologic lesions) were included in this study, with a mean age of 44.9 ± 15 years. In differentiating hematuria-dominant renal histologic lesion from the non-hematuria-dominant renal histologic lesion, the AUC value of "The ratio of the random URBC to 24-h albumin excretion" was 0.76, higher than the standard approach of Lg (URBC) [AUC = 0.744] (95% Confidence interval (CI) 0.712 ~ 0.776). The odds ratio of hematuria-dominant renal histologic lesion (Type I) increased from Q2 (3.81, 95% CI 2.66 ~ 5.50) to Q4 (14.17, 95% CI 9.09 ~ 22.72). The predictive model, composed of stratification of new composite indexes, basic demographic characteristics, and biochemical parameters, performed best with AUC value of 0.869 (95% CI 0.856-0.905). CONCLUSION: The new urinary complex indicators improved the diagnostic accuracy of hematuria and may serve as a useful parameter for screening hematuric kidney diseases.


Assuntos
Líquidos Corporais , Insuficiência Renal Crônica , Humanos , Adulto , Pessoa de Meia-Idade , Tomada de Decisão Clínica , Incerteza , Hematúria/diagnóstico , Rim , Insuficiência Renal Crônica/diagnóstico
6.
Ren Fail ; 44(1): 1169-1181, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35837696

RESUMO

Acute kidney injury (AKI) is a serious condition with high mortality. The most common cause is kidney ischemia/reperfusion (IR) injury, which is thought to be closely related to pyroptosis. Disulfiram is a well-known alcohol abuse drug, and recent studies have shown its ability to mitigate pyroptosis in mouse macrophages. This study investigated whether disulfiram could improve IR-induced AKI and elucidated the possible molecular mechanism. We generated an IR model in mouse kidneys and a hypoxia/reoxygenation (HR) injury model with murine tubular epithelial cells (MTECs). The results showed that IR caused renal dysfunction in mice and triggered pyroptosis in renal tubular epithelial cells, and disulfiram improved renal impairment after IR. The expression of proteins associated with the classical pyroptosis pathway (Nucleotide-binding oligomeric domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-related specific protein (ASC), caspase-1, N-GSDMD) and nonclassical pyroptosis pathway (caspase-11, N-GSDMD) were upregulated after IR. Disulfiram blocked the upregulation of nonclassical but not all classical pyroptosis pathway proteins (NLRP3 and ASC), suggesting that disulfiram might reduce pyroptosis by inhibiting the caspase-11-GSDMD pathway. In vitro, HR increased intracellular ROS levels, the positive rate of PI staining and LDH levels in MTECs, all of which were reversed by disulfiram pretreatment. Furthermore, we performed a computer simulation of the TIR domain of TLR4 using homology modeling and identified a small molecular binding energy between disulfiram and the TIR domain. We concluded that disulfiram might inhibit pyroptosis by antagonizing TLR4 and inhibiting the caspase-11-GSDMD pathway.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Animais , Caspases/metabolismo , Simulação por Computador , Dissulfiram/farmacologia , Isquemia , Rim/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Reperfusão , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Receptor 4 Toll-Like
7.
Mol Genet Genomics ; 296(3): 631-651, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33650010

RESUMO

Trans-Eurasian cultural and genetic exchanges have significantly influenced the demographic dynamics of Eurasian populations. The Hexi Corridor, located along the southeastern edge of the Eurasian steppe, served as an important passage of the ancient Silk Road in Northwest China and intensified the transcontinental exchange and interaction between populations on the Central Plain and in Western Eurasia. Historical and archeological records indicate that the Western Eurasian cultural elements were largely brought into North China via this geographical corridor, but there is debate on the extent to which the spread of barley/wheat agriculture into North China and subsequent Bronze Age cultural and technological mixture/shifts were achieved by the movement of people or dissemination of ideas. Here, we presented higher-resolution genome-wide autosomal and uniparental Y/mtDNA SNP or STR data for 599 northwestern Han Chinese individuals and conducted 2 different comprehensive genetic studies among Neolithic-to-present-day Eurasians. Genetic studies based on lower-resolution STR markers via PCA, STRUCTURE, and phylogenetic trees showed that northwestern Han Chinese individuals had increased genetic homogeneity relative to northern Mongolic/Turkic/Tungusic speakers and Tibeto-Burman groups. The genomic signature constructed based on modern/ancient DNA further illustrated that the primary ancestry of the northwestern Han was derived from northern millet farmer ancestors, which was consistent with the hypothesis of Han origin in North China and more recent northwestward population expansion. This was subsequently confirmed via excess shared derived alleles in f3/f4 statistical analyses and by more northern East Asian-related ancestry in the qpAdm/qpGraph models. Interestingly, we identified one western Eurasian admixture signature that was present in northwestern Han but absent from southern Han, with an admixture time dated to approximately 1000 CE (Tang and Song dynasties). Generally, we provided supporting evidence that historic Trans-Eurasian communication was primarily maintained through population movement, not simply cultural diffusion. The observed population dynamics in northwestern Han Chinese not only support the North China origin hypothesis but also reflect the multiple sources of the genetic diversity observed in this population.


Assuntos
Povo Asiático/genética , Genoma/genética , China , Cromossomos Humanos Y/genética , DNA Antigo , DNA Mitocondrial/genética , Etnicidade/genética , Genética Populacional/métodos , Estudo de Associação Genômica Ampla/métodos , Migração Humana , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único/genética
8.
Soft Matter ; 17(40): 9154-9161, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34580700

RESUMO

By incorporating a distance function into the finite element simulation, we investigate the flow-driven competition between two soft capsules passing through a narrow pore, employing the arbitrary Lagrangian-Eulerian formulation to satisfy the boundary conditions for fluid flow and capsule deformation. In our simulations, the motion and deformation of the capsules can be described in an intuitive manner, and the order in which capsules of different sizes pass through a pore can be clearly determined. Meanwhile, when the capsules are near the narrow pore, the change of the flow field is also very interesting and can be expressed intuitively. It is shown that, driven by the Poiseuille flow, the larger capsule has a stronger tendency to pass through the pore than the small one, which can be attributed to the greater resistance and the volume advantage of the larger capsule. In addition, we demonstrate that this tendency can be reversed by changing the inlet velocity and setting the initial position of the smaller capsule closer to the axis of the pore. And as long as the large one passes through first, the small one will offset the axis to the same orientation as the initial, while the large one always moves along the axis.

9.
Am J Phys Anthropol ; 174(4): 686-700, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33555039

RESUMO

OBJECTIVES: The aim of this research was to explore the origin, diversification, and demographic history of O1a-M119 over the past 10,000 years, as well as its role during the formation of East Asian and Southeast Asian populations, particularly the Han, Tai-Kadai-speaking, and Austronesian-speaking populations. MATERIALS AND METHODS: Y-chromosome sequences (n = 141) of the O1a-M119 lineage, including 17 newly generated in this study, were used to reconstruct a revised phylogenetic tree with age estimates, and identify sub-lineages. The geographic distribution of 12 O1a-M119 sub-lineages was summarized, based on 7325 O1a-M119 individuals identified among 60,009 Chinese males. RESULTS: A revised phylogenetic tree, age estimation, and distribution maps indicated continuous expansion of haplogroup O1a-M119 over the past 10,000 years, and differences in demographic history across geographic regions. We propose several sub-lineages of O1a-M119 as founding paternal lineages of Han, Tai-Kadai-speaking, and Austronesian-speaking populations. The sharing of several young O1a-M119 sub-lineages with expansion times less than 6000 years between these three population groups supports a partial common ancestry for them in the Neolithic Age; however, the paternal genetic divergence pattern is much more complex than previous hypotheses based on ethnology, archeology, and linguistics. DISCUSSION: Our analyses contribute to a better understanding of the demographic history of O1a-M119 sub-lineages over the past 10,000 years during the emergence of Han, Austronesians, Tai-Kadai-speaking populations. The data described in this study will assist in understanding of the history of Han, Tai-Kadai-speaking, and Austronesian-speaking populations from ethnology, archeology, and linguistic perspectives in the future.


Assuntos
Povo Asiático/genética , Cromossomos Humanos Y/genética , Etnicidade/genética , Genética Populacional/métodos , Haplótipos/genética , Antropologia Física , Povo Asiático/classificação , China , Etnicidade/classificação , Humanos , Masculino
10.
Ann Hum Biol ; 48(1): 49-55, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33191788

RESUMO

BACKGROUND: In recent decades, considerable attention has been paid to exploring the population genetic characteristics of Han Chinese, mainly documenting a north-south genetic substructure. However, the central Han Chinese have been largely underrepresented in previous studies. AIM: To infer a comprehensive understanding of the homogenisation process and population history of Han Chinese. SUBJECTS AND METHODS: We collected samples from 122 Han Chinese from seven counties of Hubei province in central China and genotyped 534,000 genome-wide SNPs. We compared Hubei Han with both ancient and present-day Eurasian populations using Principal Component Analysis, ADMIXTURE, f statistics, qpWave and qpAdm. RESULTS: We observed Hubei Han Chinese are at a genetically intermediate position on the north-south Han Chinese cline. We have not detected any significant genetic substructure in the studied groups from seven different counties. Hubei Han show significant evidence of genetic admixture deriving about 63% of ancestry from Tai-Kadai or Austronesian-speaking southern indigenous groups and 37% from Tungusic or Mongolic related northern populations. CONCLUSIONS: The formation of Han Chinese has involved extensive admixture with Tai-Kadai or Austronesian-speaking populations in the south and Tungusic or Mongolic speaking populations in the north. The convenient transportation and central location of Hubei make it the key region for the homogenisation of Han Chinese.


Assuntos
Etnicidade/genética , Genótipo , Migração Humana , Polimorfismo de Nucleotídeo Único , China , Humanos , Análise de Componente Principal
11.
Proc Natl Acad Sci U S A ; 114(14): 3648-3653, 2017 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-28320962

RESUMO

Genetic lesions that activate KRAS account for ∼30% of the 1.6 million annual cases of lung cancer. Despite clinical need, KRAS is still undruggable using traditional small-molecule drugs/inhibitors. When oncogenic Kras is suppressed by RNA interference, tumors initially regress but eventually recur and proliferate despite suppression of Kras Here, we show that tumor cells can survive knockout of oncogenic Kras, indicating the existence of Kras-independent survival pathways. Thus, even if clinical KRAS inhibitors were available, resistance would remain an obstacle to treatment. Kras-independent cancer cells exhibit decreased colony formation in vitro but retain the ability to form tumors in mice. Comparing the transcriptomes of oncogenic Kras cells and Kras knockout cells, we identified 603 genes that were specifically up-regulated in Kras knockout cells, including the Fas gene, which encodes a cell surface death receptor involved in physiological regulation of apoptosis. Antibodies recognizing Fas receptor efficiently induced apoptosis of Kras knockout cells but not oncogenic Kras-expressing cells. Increased Fas expression in Kras knockout cells was attributed to decreased association of repressive epigenetic marks at the Fas promoter. Concordant with this observation, treating oncogenic Kras cells with histone deacetylase inhibitor and Fas-activating antibody efficiently induced apoptosis, thus bypassing the need to inhibit Kras. Our results suggest that activation of Fas could be exploited as an Achilles' heel in tumors initiated by oncogenic Kras.


Assuntos
Anticorpos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor fas/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Epigênese Genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Camundongos , Mutação , Transplante de Neoplasias , Regiões Promotoras Genéticas , Regulação para Cima
12.
Ann Hum Biol ; 47(5): 465-471, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32543893

RESUMO

BACKGROUND: Chuanqing is an unrecognised ethnic group in Guizhou, southwest China. The genetic history of the Chuanqing people is hotly debated due to a lack of available genetic data. AIM: To infer the genetic structure and population history of the Chuanqing people and genetic relationships of the Chuanqing with other East Asians. SUBJECTS AND METHODS: We collected samples from 14 Chuanqing individuals from Guizhou and genotyped about 690,000 genome-wide single nucleotide polymorphisms (SNPs). We used Principal Component Analysis (PCA), ADMIXTURE analysis, and f statistics to infer the population genetic structure and admixture. RESULTS: Chuanqing people show a distinct genetic profile from indigenous Tai-Kadai and Tibeto-Burman speaking populations in southwest China, but they are genetically similar to southern Han Chinese, Miao, She and Tujia populations. The Han Chinese characteristic Y chromosomal lineages reach high frequencies in the Chuanqing. CONCLUSIONS: The genetic formation of the Chuanqing people has been greatly influenced by Han Chinese related populations.


Assuntos
Etnicidade/genética , Genoma Humano , Genótipo , Polimorfismo de Nucleotídeo Único , China/etnologia , Humanos
13.
Ann Hum Biol ; 47(7-8): 620-628, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33059477

RESUMO

BACKGROUND: Mongolian populations are widely distributed geographically, showing abundant ethnic diversity with geographic and tribal differences. AIM: To infer the genetic substructure, admixture and ancient genetic sources of Mongolians together with Kazakhs. SUBJECTS AND METHODS: We genotyped more than 690,000 genome-wide SNPs from 33 Mongolian and Chinese Kazakh individuals and compared these with both ancient and present-day Eurasian populations using Principal Component Analysis (PCA), ADMIXTURE, Refine-IBD, f statistics, qpWave and qpAdm. RESULTS: We found genetic substructures within Mongolians corresponding to Ölöd, Chahar, and Inner Mongolian clusters, which was consistent with tribe classifications. Mongolian and Kazakh groups derived about 6-40% of West Eurasian related ancestry, most likely from Bronze Age Steppe populations. The East Asian related ancestry in Mongolian and Kazakh groups was well represented by the Neolithic DevilsCave related nomadic lineage, comprising 42-64% of studied groups. We also detected 10-51% of Han Chinese related ancestry in Mongolian and Kazakh groups, especially in Inner Mongolians. The average admixture times for Inner Mongolian, Mongolian_Chahar, Mongolian_Ölöd and Chinese Kazakh were about 1381, 626, 635 and 632 years ago, respectively, with Han and French as the sources. CONCLUSION: The DevilsCave related ancestry was once widespread westwards covering a wide geographical range from Far East Russia to the Mongolia Plateau. The formation of present-day Mongolic and Turkic-speaking populations has also received genetic influence from agricultural expansion.


Assuntos
Genótipo , Polimorfismo de Nucleotídeo Único , China/etnologia , Feminino , Humanos , Cazaquistão/etnologia , Masculino , Mongólia/etnologia
14.
Gastroenterology ; 152(5): 1161-1173.e1, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27956228

RESUMO

BACKGROUND & AIMS: It has been a challenge to identify liver tumor suppressors or oncogenes due to the genetic heterogeneity of these tumors. We performed a genome-wide screen to identify suppressors of liver tumor formation in mice, using CRISPR-mediated genome editing. METHODS: We performed a genome-wide CRISPR/Cas9-based knockout screen of P53-null mouse embryonic liver progenitor cells that overexpressed MYC. We infected p53-/-;Myc;Cas9 hepatocytes with the mGeCKOa lentiviral library of 67,000 single-guide RNAs (sgRNAs), targeting 20,611 mouse genes, and transplanted the transduced cells subcutaneously into nude mice. Within 1 month, all the mice that received the sgRNA library developed subcutaneous tumors. We performed high-throughput sequencing of tumor DNA and identified sgRNAs increased at least 8-fold compared to the initial cell pool. To validate the top 10 candidate tumor suppressors from this screen, we collected data from patients with hepatocellular carcinoma (HCC) using the Cancer Genome Atlas and COSMIC databases. We used CRISPR to inactivate candidate tumor suppressor genes in p53-/-;Myc;Cas9 cells and transplanted them subcutaneously into nude mice; tumor formation was monitored and tumors were analyzed by histology and immunohistochemistry. Mice with liver-specific disruption of p53 were given hydrodynamic tail-vein injections of plasmids encoding Myc and sgRNA/Cas9 designed to disrupt candidate tumor suppressors; growth of tumors and metastases was monitored. We compared gene expression profiles of liver cells with vs without tumor suppressor gene disrupted by sgRNA/Cas9. Genes found to be up-regulated after tumor suppressor loss were examined in liver cancer cell lines; their expression was knocked down using small hairpin RNAs, and tumor growth was examined in nude mice. Effects of the MEK inhibitors AZD6244, U0126, and trametinib, or the multi-kinase inhibitor sorafenib, were examined in human and mouse HCC cell lines. RESULTS: We identified 4 candidate liver tumor suppressor genes not previously associated with liver cancer (Nf1, Plxnb1, Flrt2, and B9d1). CRISPR-mediated knockout of Nf1, a negative regulator of RAS, accelerated liver tumor formation in mice. Loss of Nf1 or activation of RAS up-regulated the liver progenitor cell markers HMGA2 and SOX9. RAS pathway inhibitors suppressed the activation of the Hmga2 and Sox9 genes that resulted from loss of Nf1 or oncogenic activation of RAS. Knockdown of HMGA2 delayed formation of xenograft tumors from cells that expressed oncogenic RAS. In human HCCs, low levels of NF1 messenger RNA or high levels of HMGA2 messenger RNA were associated with shorter patient survival time. Liver cancer cells with inactivation of Plxnb1, Flrt2, and B9d1 formed more tumors in mice and had increased levels of mitogen-activated protein kinase phosphorylation. CONCLUSIONS: Using a CRISPR-based strategy, we identified Nf1, Plxnb1, Flrt2, and B9d1 as suppressors of liver tumor formation. We validated the observation that RAS signaling, via mitogen-activated protein kinase, contributes to formation of liver tumors in mice. We associated decreased levels of NF1 and increased levels of its downstream protein HMGA2 with survival times of patients with HCC. Strategies to inhibit or reduce HMGA2 might be developed to treat patients with liver cancer.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Hepatócitos/metabolismo , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteína Supressora de Tumor p53/genética , Animais , Benzimidazóis/farmacologia , Western Blotting , Butadienos/farmacologia , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Proteínas do Citoesqueleto , DNA de Neoplasias/genética , Inibidores Enzimáticos , Genes da Neurofibromatose 1 , Estudo de Associação Genômica Ampla , Proteínas HMGA/genética , Proteína HMGA2/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Camundongos Nus , Proteínas do Tecido Nervoso/genética , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Nitrilas/farmacologia , Compostos de Fenilureia/farmacologia , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Piridonas/farmacologia , Pirimidinonas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Superfície Celular/genética , Análise de Sequência de DNA , Sorafenibe , Análise de Sobrevida , Proteínas Supressoras de Tumor/genética , Proteínas ras/genética
15.
Nature ; 490(7418): 49-54, 2012 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-22992520

RESUMO

The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa.


Assuntos
Adaptação Fisiológica/genética , Exoesqueleto/crescimento & desenvolvimento , Crassostrea/genética , Genoma/genética , Estresse Fisiológico/fisiologia , Exoesqueleto/química , Animais , Proteínas Reguladoras de Apoptose/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Genes Homeobox/genética , Genômica , Proteínas de Choque Térmico HSP70/genética , Humanos , Larva/genética , Larva/crescimento & desenvolvimento , Espectrometria de Massas , Anotação de Sequência Molecular , Dados de Sequência Molecular , Polimorfismo Genético/genética , Sequências Repetitivas de Ácido Nucleico/genética , Análise de Sequência de DNA , Estresse Fisiológico/genética , Transcriptoma/genética
16.
Acta Pharmacol Sin ; 39(5): 866-874, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29417943

RESUMO

Epigenetic gene-regulation abnormalities have been implicated in various neuropsychiatric disorders including schizophrenia and depression, as well as in the regulation of mood and anxiety. In addition, epigenetic mechanisms are involved in the actions of psychiatric drugs. Current anxiolytic drugs have significant shortcomings, and development of new medications is warranted. Two proteins, G9a (also known as EHMT2 or KMT1C) and GLP (G9a-like protein, also known as EHMT1 or KMT1D), which methylate lysine 9 of histone H3 (H3K9), could be promising anxiolytic targets. Postnatal genetic knock-out of G9a reduces anxiety-related behavior, consistent with the reduction of G9a levels by some medications used to treat anxiety (amitriptyline, imipramine and paroxetine). Conversely, there is increased anxiety-like behavior in mice with GLP haplodeficiency. We sought to determine whether two pharmacological inhibitors of G9a/GLP, UNC0642 and A-366, would have similar effects to genetic G9a/GLP insufficiency. We found that G9a/GLP inhibition with either compound reduced anxiety-like behaviors when administered to adult mice, in conjunction with decreased H3K9 methylation in the brain. In contrast, exposure to these compounds from embryonic day 9.5 (E9.5) until birth increased anxiety-like behaviors and decreased social interaction in adulthood, while H3K9 methylation was at normal levels in the brains of the adult mice. These findings reinforce genetic evidence that G9a/GLP has different effects on anxiety-like behavior at different stages of brain development, and suggest that targeting this histone methyltransferase pathway could be useful for developing new anxiolytic drugs. These data also suggest that antidepressant exposure in utero could have negative effects in adulthood, and further investigation of these effects is warranted.


Assuntos
Ansiolíticos/uso terapêutico , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Indóis/uso terapêutico , Quinazolinas/uso terapêutico , Compostos de Espiro/uso terapêutico , Animais , Diazepam/uso terapêutico , Relação Dose-Resposta a Droga , Epigênese Genética , Feminino , Histonas/genética , Histonas/metabolismo , Masculino , Metilação , Camundongos Endogâmicos C57BL , Processamento de Proteína Pós-Traducional , Cloridrato de Venlafaxina/uso terapêutico
17.
Am J Phys Anthropol ; 166(3): 638-648, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29492966

RESUMO

OBJECTIVES: The Jing people are a recognized ethnic group in Guangxi, southwest China, who are the immigrants from Vietnam during the 16th century. They speak Vietnamese but with lots of language borrowings from Cantonese, Zhuang, and Mandarin. However, it's unclear if there is large-scale gene flow from surrounding populations into Jing people during their language change due to the very limited genetic information of this population. MATERIALS AND METHODS: We collected blood samples from 37 Jing and 3 Han Chinese individuals from Wanwei, Shanxin, and Wutou islands in Guangxi and genotyped about 600,000 genome-wide single nucleotide polymorphisms (SNPs). We used Principal Component Analysis (PCA), ADMIXTURE analysis, f statistics, qpWave and qpAdm to infer the population genetic structure and admixture. RESULTS: Our data revealed that the Jing people are genetically similar to the populations in southwest China and mainland Southeast Asia. But compared with Vietnamese, they show significant evidence of gene flow from surrounding East Asians. The admixture proportion is estimated to be around 35-42% in different Jing groups using southern Han Chinese as a proxy. The majority of the paternal lineages of Jing people are most likely from surrounding East Asians. DISCUSSION: We conclude that the formation and language change of present-day Jing people have involved genetic assimilation of surrounding East Asian populations. The language borrowing, in this case, is not only a cultural phenomenon but has involved demic diffusion.


Assuntos
Povo Asiático/genética , Fluxo Gênico/genética , Idioma , Antropologia Física , China/etnologia , Feminino , Genética Populacional , Humanos , Masculino , Análise de Componente Principal , Vietnã/etnologia
18.
ACS Macro Lett ; 13(8): 1022-1030, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39074066

RESUMO

Herein, an ω,ω-macromolecular chain transfer monomer (macro-CTM) containing a RAFT (reversible addition-fragmentation chain transfer) group and a methacryloyl group was synthesized and used to mediate photoinitiated RAFT dispersion polymerization of hydroxypropyl methacrylate (HPMA) in water. The macro-CTM undergoes a self-condensing vinyl polymerization (SCVP) mechanism under RAFT dispersion polymerization conditions, leading to the formation of amphiphilic branched block copolymers and the assemblies. Compared with RAFT solution polymerization, it was found that the SCVP process was promoted under RAFT dispersion polymerization conditions. Morphologies of branched block copolymer assemblies could be controlled by varying the monomer concentration and the [HPMA]/[macro-CTM] ratio. The branched block copolymer vesicles could be used as seeds for seeded RAFT emulsion polymerization, and framboidal vesicles were successfully obtained. Finally, degrees of branching of branched block copolymers could be further controlled by using a binary mixture of the macro-CTM and a linear macro-RAFT agent or a small molecule CTM. We believe that this study not only provides a versatile strategy for the preparation of branched block copolymer assemblies but also offers important insights into polymer synthesis via heterogeneous RAFT polymerization.

19.
Trends Cancer ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39394009

RESUMO

Brain tumors in children and adults differ greatly in patient outcomes and responses to radiotherapy and chemotherapy. Moreover, the prevalence of recurrent mutations in histones and chromatin regulatory proteins in pediatric and young adult gliomas suggests that the chromatin landscape is rewired to support oncogenic programs. These early somatic mutations dysregulate widespread genomic loci by altering the distribution of histone post-translational modifications (PTMs) and, in consequence, causing changes in chromatin accessibility and in the histone code, leading to gene transcriptional changes. We review how distinct chromatin imbalances in glioma subtypes impact on oncogenic features such as cellular fate, proliferation, immune landscape, and radio resistance. Understanding these mechanisms of epigenetic dysregulation carries substantial implications for advancing targeted epigenetic therapies.

20.
Heliyon ; 9(11): e22431, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034613

RESUMO

Epilepsy is an intractable chronic neurological disease attached to extensive attention. Due to the fact that unpredictable seizure attacks result in serious physical injuries, early warning before seizure occurrence can help patients to get timely treatment and intervention. This paper presents a novel patient-specific method to predict epileptic seizures by learning shapelets of scalp electroencephalogram (EEG) signals recorded from different channels. In the proposed method, EEG signals are preprocessed to raise the Signal to Noise Rate (SNR). Multichannel shapelets space is constructed by the learning-near-to-optimal shapelets method. EEG signals are converted to distance matrices by projecting them on the shapelets' space. Bi-LSTM, SVM, CNN, and an ensemble of them are used to classify the feature set. Based on the prediction results then raise alarms. The proposed methodology is applied to the CHB-MIT scalp EEG dataset of 10 cases. The proposed method achieves a sensitivity of 91.33% and a false prediction rate of 0.16 h-1.

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