Caracterização do papel de Nop53 na montagem da subunidade ribossomal maior em Saccharomyces cerevisiae / Characterization of the role of Nop53 in the assembly of the large ribosomal subunit in Saccharomyces cerevisiae

Os ribossomos são complexos ribonucleoproteicos conservados formados por duas subunidades assimétricas (40S e 60S em eucariotos) responsáveis pela tradução da informação genética e catálise da síntese proteica. A montagem destes complexos em eucariotos é mais bem descrita em S. cerevisiae, constituindo um processo celular energeticamente dispendioso e com múltiplas etapas. Ela tem origem no nucléolo com a transcrição do pré-rRNA 35S e requer o recrutamento hierárquico e transiente de cerca de 200 fatores de montagem para garantir a formação correta dos centros funcionais aptos à tradução. Neste processo, que se estende no núcleo e citoplasma, 79 proteínas ribossomais associam-se gradativamente à medida que o prérRNA é dobrado, modificado e processado. O processamento do pré-rRNA 35S consiste na remoção progressiva de espaçadores internos (ITS1 e ITS2) e externos (5ETS e 3ETS), que separam e flanqueiam os rRNAs maduros componentes de ambas subunidades ribossomais. A clivagem do ITS1 separa as vias de maturação do pré-60S e do pré-40S. O ITS2, que, em associação a fatores de montagem, forma uma estrutura denominada ITS2-foot, é o último espaçador do pré-60S a ser removido. A composição do ITS2-foot permanece inalterada no nucléolo até a transição entre o estado E nucleolar e a formação da partícula Nog2 nuclear. Nesta etapa, a liberação do fator Erb1 permite o recrutamento do fator de montagem conservado e essencial Nop53. Na base do ITS2-foot, Nop53 recruta o exossomo via RNA helicase Mtr4 para a clivagem 3-5 exonucleolítica de parte do ITS2 levando à desmontagem do ITS2-foot. O fato de Nop53 atuar como ponte entre dois grandes complexos e apresentar uma estrutura flexível e estendida nos levou a aprofundar a caracterização de seu papel durante a maturação do pré60S. Neste trabalho, usando análise proteômica quantitativa label-free baseada em espectrometria de massas, caracterizou-se o interactoma de Nop53, e avaliou-se o impacto da depleção de Nop53 no interactoma da subunidade catalítica do exossomo Rrp6 e na composição de pré-ribossomos representativos de quase todas as etapas de maturação do pré-60S. Em paralelo, foram caracterizados mutantes truncados de Nop53 e avaliada por pull-down a interação de Nop53 com componentes do exossomo. Os resultados obtidos mostraram que Nop53 é capaz de interagir com o cofator do exossomo Mpp6, sugerindo pontos adicionais de interação durante o recrutamento do exossomo ao pré-60S. A análise do interactoma de Rrp6 mostrou uma associação precoce do exossomo aos intermediários pré-ribossomais nucleolares mais iniciais, anteriores aos previamente descritos. Mudanças na composição dos intermediários pré-60S revelaram que a depleção de Nop53 afeta a transição entre o estado E e a partícula Nog2, afetando eventos tardios de maturação como o recrutamento de Yvh1. Comparando-se o efeito da depleção de Nop53 com o de mutantes nop53 desprovidos da região de recrutamento do exossomo, obtivemos evidências bioquímicas do papel estrutural de Nop53 na base do ITS2- foot. Em conjunto, estas observações, à luz de estruturas de intermediários pré-ribossomais recentemente descritas, nos permitiram concluir que o recrutamento de Nop53 ao pré-60S contribui para a estabilização de eventos de remodelamento do rRNA que antecedem a formação da partícula Nog2

Ribosomes are conserved ribonucleoprotein complexes formed by two asymmetric subunits (the 40S and the 60S in eukaryotes) responsible for translating the genetic information and catalyzing protein synthesis. The assembly of these complexes in eukaryotes is best described in S. cerevisiae. It is an energetically demanding, multi-step cellular process, that starts in the nucleolus with the transcription of the 35S pre-rRNA. It requires the hierarchical and transient recruitment of about 200 assembly factors to ensure the correct formation of the functional centers suitable for translation. In this process, which extends into the nucleus and cytoplasm, 79 ribosomal proteins gradually associate as the pre-rRNA is folded, modified, and processed. The 35S pre-rRNA processing happens with the progressive removal of internal (ITS1 and ITS2) and external (5'ETS and 3'ETS) transcribed spacers, which separate and flank the mature rRNA components of both ribosomal subunits. The cleavage at the ITS1 separates the pre-60S and pre40S maturation pathways. The ITS2, which in association with assembly factors constitutes a structure called ITS2-foot, is the last pre-60S spacer to be removed. The composition of the ITS2- foot remains unchanged in the nucleolus until the transition between the nucleolar state E and the nuclear Nog2 particle. At this stage, the release of Erb1 allows the recruitment of the conserved and essential assembly factor Nop53. At the base of the ITS2-foot, Nop53 recruits the exosome via the RNA helicase Mtr4 for the ITS2 3'-5' exonucleolytic cleavage leading to the ITS2-foot disassembly. The fact that Nop53 acts as a bridge between these two large complexes and exhibits a flexible and extended structure led us to further characterize its role in the pre-60S maturation. In this work, using mass spectrometry-based label-free quantitative proteomics, we characterized the interactome of Nop53, as well as the impact of the depletion of Nop53 on the interactome of the exosome catalytic subunit Rrp6 and on the composition of pre-ribosomes representative of almost all pre-60S maturation stages. In parallel, we characterized nop53 truncated mutants and evaluated the interaction of Nop53 with exosome components by pulldown assays. The results showed that Nop53 can interact with the exosome cofactor Mpp6, suggesting the contribution of additional points of interaction during the exosome recruitment to the pre-60S. The analysis of the Rrp6 interactome revealed an early association of the exosome with pre-ribosomal intermediates at very early nucleolar stages, before those previously described. Changes in the composition of pre-60S intermediates revealed that Nop53 depletion affects the transition between the state E and the Nog2 particle, affecting late pre-60S maturation events, such as the Yvh1 recruitment. Comparing the effect of Nop53 depletion with that of nop53 mutants lacking the exosome interacting region, we obtained biochemical evidence of the structural role of Nop53 at the base of the ITS2-foot. Altogether, and in light of recently described structures of pre-ribosomal intermediates, these observations allowed us to conclude that the recruitment of Nop53 to the pre-60S contributes to the stabilization of rRNA remodeling events that precede the formation of the Nog2 particle

Exploration of the therapeutic mechanism of Yiqi Jiedu recipe for treatment of primary liver cancer based on network pharmacology and molecular docking / 南方医科大学学报

OBJECTIVE@#To explore the effective components of Yiqi Jiedu recipe and the main biological processes and signal pathways involved in the therapeutic mechanism of the recipe in treatment of primary liver cancer through network pharmacology and molecular docking approaches.@*METHODS@#TCMSP, Uniport, Genecards and String databases were searched to obtain the target genes of drugs and disease using Cytoscape 3.8.2 software. GO and KEGG enrichment analyses were performed to identify the common genes in the target genes of the drugs and disease. Using Pubcham, RCSB and Autoduck, the effective components of the drugs were connected with the final core genes. The effects of different concentrations of Yiqi Jiedu recipe on the expressions of the core genes DHX9, HNRNPK, NCL and PABPC1 in HepG2 cells were analyzed with Western blotting and real- time fluorescence quantitative PCR.@*RESULTS@#We finally identified 8 core genes from the drug and disease targets, including DDX5, HNRNPK, PABPC1, DHX9, RPS3A, RPS3, RPL13, and NCL. GO analysis showed that these core genes were involved mainly in the biological processes of adrenaline receptor signal communication, movement of cellular or subcellular components, blood particles, adhesion class and iron ion binding. KEGG analysis showed that the Ras signaling pathway had the greatest gene enrichment. The results of molecular docking suggested that the effective components of the recipe were capable of docking with the core genes under natural conditions, and PABPC1 and stigmasterol had the highest binding energy. In HepG2 cells, treatment with 10% medicated serum for 48 h had the strongest effect on the expression of DHX9, HNRNPK, NCL and PABPC1 (P < 0.05).@*CONCLUSION@#Yiqi Jiedu recipe is capable of regulating viral expression of primary liver cancer multiple effective components that bind to DHX9, HNRNPK, NCL and PABPC1.

Knockout of ribosomal genes bS22 and bL37 increases the sensitivity of mycobacteria to antibiotics / 生物工程学报

In recent years, two novel proteins in the ribosomes of mycobacteria have been discovered by cryo-electron microscopy. The protein bS22 is located near the decoding center of the 30S subunit, and the protein bL37 is located near the peptidyl transferase center of the 50S subunit. Since these two proteins bind to conserved regions of the ribosome targeted by antibiotics, it is speculated that they might affect the binding of related drugs to these targets. Therefore, we knocked out the genes encoding these two proteins in wild-type Mycolicibacterium smegmatis mc2155 through homologous recombination, and then determined the growth curves of these mutants and their sensitivity to related antibiotics. The results showed that compared with the wild-type strain, the growth rate of these two mutants did not change significantly. However, mutant ΔbS22 showed increased sensitivity to capreomycin, kanamycin, amikacin, streptomycin, gentamicin, paromomycin, and hygromycin B, while mutant ΔbL37 showed increased sensitivity to linezolid. These changes in antibiotics sensitivity were restored by gene complementation. This study hints at the possibility of using ribosomal proteins bS22 and bL37 as targets for drug design.

Ionizing Radiation-Induced RPL23a Reduction Regulates Apoptosis / 生物医学与环境科学（英文）

Objective@#The expression patterns of ribosomal large subunit protein 23a (RPL23a) in mouse testes and GC-1 cells were analyzed to investigate the potential relationship between RPL23a expression and spermatogonia apoptosis upon exposure to X-ray.@*Methods@#Male mice and GC-1 cells were irradiated with X-ray, terminal dUTP nick end-labelling (TUNEL) was performed to detect apoptotic spermatogonia @*Results@#Ionizing radiation (IR) increased spermatogonia apoptosis, the expression of RPL11, MDM2 and p53, and decreased RPL23a expression in mice spermatogonia @*Conclusion@#These results suggested that IR reduced RPL23a expression, leading to weakened the RPL23a-RPL11 interactions, which may have activated p53, resulting in spermatogonia apoptosis. These results provide insights into environmental and clinical risks of radiotherapy following exposure to IR in male fertility. The graphical abstract was available in the web of www.besjournal.com.

Linezolid Resistance in Methicillin-Resistant Staphylococcus aureus in Korea: High Rate of False Resistance to Linezolid by the VITEK 2 System

As various linezolid resistance mechanisms have been identified in methicillin-resistant Staphylococcus aureus (MRSA), we investigated the molecular characteristics of MRSA with elevated linezolid minimum inhibitory concentrations (MICs), using the VITEK 2 system (bioMérieux, Marcy-l'Étoile, France). Twenty-seven MRSA isolates from 14 patients exhibiting linezolid MICs ≥8 µg/mL were examined by broth microdilution (BMD) test as well as by sequencing for mutations in the 23S rRNA gene or ribosomal proteins (L3, L4, and L22) and the presence of the optrA, cfr, and cfr(B) genes. Of the 27 isolates, four (14.8%) from one patient were confirmed as linezolid resistant by BMD and harbored a 23S rRNA T2500A mutation. The remaining 23 were confirmed as linezolid susceptible, indicating that the linezolid-resistant results were major errors generated by VITEK 2. The most commonly detected mutation (19/27, 70.4%), L3 Gly152Asp, was detected in only linezolid-susceptible isolates. No isolates contained optrA, cfr, or cfr(B) or any L4 or L22 protein alterations. Our results show that the 23S rRNA T2500A mutation was mainly associated with linezolid resistance, while the L3 Gly152Asp mutation was not related to linezolid resistance. A confirmatory test is recommended for VITEK 2 linezolid-resistant results owing to the high probability of false resistant results.

Molecular Epidemiology and Mechanisms of 43 Low-Level Linezolid-Resistant Enterococcus faecalis Strains in Chongqing, China

BACKGROUND: Enterococcus faecalis strains with low-level resistance to linezolid (an oxazolidinone antibiotic) have become common. No large-scale study has examined the underlying mechanisms in linezolid-resistant E. faecalis (LRE) strains. We investigated these mechanisms and molecular characteristics in Chongqing, China. METHODS: A total of 1,120 non-duplicated E. faecalis strains collected from August 2014 to June 2017 underwent drug susceptibility testing. LRE strains were screened for optrA, cfr, and mutations in the 23S rRNA and ribosomal proteins L3 and L4 by PCR amplification and sequencing. Multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used for epidemiological analysis. RESULTS: All 43 low-level LRE strains (minimum inhibitory concentration: 8–16 mg/L) harbored optrA; cfr and 23S rRNA mutations were not detected. Novel mutations in the ribosomal proteins L3 and L4—one deletion (Q103del) and four substitutions (S113L, T35A, I98V, and N79D)—were identified. Novel amino acid substitutions at positions E60K, G197D, and T285P of the OptrA protein were observed. MLST revealed 20 types of LRE strains; the most common type was ST16 (32.6%). PFGE showed 14 strains of ST16 with unique banding patterns. Eight novel sequence types (ST823 to ST830) and one allele (gki95) were identified for the first time in China. CONCLUSIONS: optrA plays an important role in linezolid resistance and may serve as a marker for resistance screening. Since the L3 and L4 mutations did not simultaneously occur in the same strain, they play a negligible role in linezolid resistance. Epidemiological investigation suggested that the LRE cases were sporadic.

Identification of the targets of hematoporphyrin derivative in lung adenocarcinoma using integrated network analysis

BACKGROUND: Hematoporphyrin derivative (HPD) has a sensibilization effect in lung adenocarcinoma. This study was conducted to identify the target genes of HPD in lung adenocarcinoma. METHODS: RNA sequencing was performed using the lung adenocarcinoma cell line A549 after no treatment or treatment with X-ray or X-ray + HPD. The differentially expressed genes (DEGs) were screened using Mfuzz package by noise-robust soft clustering analysis. Enrichment analysis was carried out using "BioCloud" online tool. Protein-protein interaction (PPI) network and module analyses were performed using Cytoscape software. Using WebGestalt tool and integrated transcription factor platform (ITFP), microRNA target and transcription factor (TF) target pairs were separately predicted. An integrated regulatory network was visualized with Cytoscape software. RESULTS: A total of 815 DEGs in the gene set G1 (continuously dysregulated genes along with changes in processing conditions [untreated-treated with X-ray-X-ray + treated with HPD]) and 464 DEGs in the gene set G2 (significantly dysregulated between X-ray + HPD-treated group and untreated/X-ray-treated group) were screened. The significant module identified from the PPI network for gene set G1 showed that ribosomal protein L3 (RPL3) gene could interact with heat shock protein 90 kDa alpha, class A member 1 (HSP90AA1). TFs AAA domain containing 2 (ATAD2) and protein inhibitor of activated STAT 1 (PIAS1) were separately predicted for the genes in gene set G1 and G2, respectively. In the integrated network for gene set G2, ubiquitin-specific peptidase 25 (USP25) was targeted by miR-200b, miR-200c, and miR-429. CONCLUSION: RPL3, HSP90AA1, ATAD2, and PIAS1 as well as USP25, which is targeted by miR-200b, miR-200c, and miR-429, may be the potential targets of HPD in lung adenocarcinoma.

Ribosomal Protein S9 Expression in Multiple Myeloma and Its Effect on Cell Biological Function / 中国医学科学院学报

Objective To identify the expression of ribosomal protein S9(RPS9)in multiple myeloma(MM)and explore its effect on the biological characteristics of myeloma cells and the corresponding mechanisms. Methods Bone marrow mononuclear cells were harvested in 10 healthy volunteers(CON group)and bone marrow CD138 +cells from 30 MM patients(CD138+group).Quantitative polymerase chain reaction(qPCR)was performed to detect RPS9 expression at mRNA level.In three cases from CON group and 11 cases from CD138+group,Western blot was performed to detect RPS9 at protein level.GSE19784 dataset was employed to detect the relationships of RPS9 expression with the overall survival rate,nuclear factor-κB(NF-κB),small ubiquitin-like modifier(SUMO),and ubiquitin pathway.After the RPS9 knock-down vector was constructed,flow cytometry was performed to detect the infection efficiency and qPCR and Western blot to detect the knock-down efficiency.RPMI8226 was divided into CON group and RPS9-short hairpin RNA(shRNA)group,in which annexin V allophycocyanin/propidium iodide(PI)double staining was performed to detect the change of apoptosis,CCK8 to detect the proliferation change,and PI staining to detect cell cycle change.After sentrin-specific protease 1(SENP1)overexpression vector was constructed,Western blot was performed to detect the phosphorylation of P65 and inhibitory subunit-κBα(IκBα)from NF-κB pathway in CON,RPS9-shRNA,and RPS9-shRNA-SENP1 cells;in addition,annexin V/PI double staining was also performed to detect the apoptosis in these three cells. Results The relative expression of RPS9 in CON group and CD138+group was(1.00±0.12)and(5.45±0.71),respectively(t=4.291,P=0.0036).Western blot showed RPS9 expression was high in most myeloma CD138+cells.The high expression of RPS9 was associated with both extramedullary invasion and overall survival in GSE19784 dataset.After RPMI8226 was infected with CON or RPS9-shRNA lentivirus for 48 hours,flow cytometry confirmed that the infection efficiencies were above 90% in both groups.qPCR and Western blot confirmed that RPS9 expression was inhibited at both mRNA and protein levels.After RPMI8226 CON and RPS9-shRNA infected with virus for 48 hours,the proportion of annexin V-positive cells in CON and RPS9-shRNA cells was(3.47±0.37)% and(18.60±64.00)%(t=9.015,P=0.0008).The proliferation index significantly differed between CON group and RPS9-shRNA group at 72 hours(t=6.846,P=0.0024).When CON and RPS9-shRNA were infected with virus for 48 hours,the proportion of G2 phase cells was(29.28±3.42)% and(10.43±1.43)%,respectively(t=9.329,P=0.0007).The RPS9 expression was positively correlated with SENP1 in GSE19784 dataset and negatively correlated with IκBα coding gene NFKBIA.Western blot further confirmed that RPS9 knockdown inhibited the expression of SENP1,inhibited the phosphorylation of NF-κB subunit P65 and inhibitor IκBα,and promoted the expression of IκBα.Overexpression of SENP1 not only impeded this effect but also reduced RPS9-induced apoptosis. Conclusions RPS9 is highly expressed in MM CD138+cells and is associated with overall survival and extramedullary infiltration.Inhibition of RPS9 can promote apoptosis,cell cycle arrest,and proliferation of myeloma cells.RPS9 can affect the activation of NF-κB pathway and cell apoptosis through SENP1,suggesting that SENP1 may be a key factor in the biological effect of RPS9.

RNF138-mediated ubiquitination of rpS3 is required for resistance of glioblastoma cells to radiation-induced apoptosis

An interaction between ribosomal protein S3 (rpS3) and nuclear factor kappa B or macrophage migration inhibitory factor in non-small-cell lung cancer is responsible for radioresistance. However, the role of rpS3 in glioblastoma (GBM) has not been investigated to date. Here we found that in irradiated GBM cells, rpS3 translocated into the nucleus and was subsequently ubiquitinated by ring finger protein 138 (RNF138). Ubiquitin-dependent degradation of rpS3 consequently led to radioresistance in GBM cells. To elucidate the apoptotic role of rpS3, we analyzed the interactome of rpS3 in ΔRNF138 GBM cells. Nuclear rpS3 interacted with DNA damage inducible transcript 3 (DDIT3), leading to DDIT3-induced apoptosis in irradiated ΔRNF138 GBM cells. These results were confirmed using in vivo orthotopic xenograft models and GBM patient tissues. This study aims to clarify the role of RNF138 in GBM cells and demonstrate that rpS3 may be a promising substrate of RNF138 for the induction of GBM radioresistance, indicating RNF138 as a potential target for GBM therapy.

RPS15a Silencing Suppresses Cell Proliferation and Migration of Gastric Cancer

PURPOSE: Information on the possible role of the ribosomal protein S15a (RPS15a) in gastric cancer is scarce. The aim of this study was to evaluate the impact of RPS15a gene expression on the growth and cell cycle of gastric cancer cells in vitro and in vivo. MATERIALS AND METHODS: RPS15a mRNA expression was examined in cancer tissues and their corresponding adjacent normal tissues of 40 gastric adenocarcinoma patients. Next, RPS15a was knocked down using a lentivirus-mediated RNA interference (short hairpin RNA) system in the gastric cancer cell line BGC823. The effect of RPS15a knockdown was examined using CCK-8 assay, cell scratch test, colony formation assay, and flow cytometry. Finally, in nude mice, a tumorigenicity test was performed, and the tumor volume and weight were measured. RESULTS: RPS15a expression in tumor tissue was significantly greater than that in the adjacent normal tissue of gastric cancer patients. After RPS15a silencing, the BGC823 cell proliferation rate decreased significantly; most cells were arrested in the G0/G1 phase, cell growth was inhibited, and the migration rate was decreased. Colony formation assay showed that the number and size of clones in the RPS15a-silenced cells were fewer and smaller, compared to control cells. The nude mouse tumorigenicity test showed that RPS15a silencing had an inhibitory effect on tumor volume and mice weight. CONCLUSION: The present study found RPS15a expression to be higher in gastric tumors and its silencing in gastric cancer cells to inhibit the proliferation, growth, and migration thereof. Accordingly, RPS15a may be considered as a potential therapeutic target in gastric cancer.

Omadacycline, a Magic Antibiotics for Bacterial Infections

Nowadays antibiotic resistance is a worldwide serious problem that mainly affects public health. Omadacycline is a unique antibiotic which has two available dosage forms such as intravenous (IV) and oral that development for community-acquired bacterial infectious disease treatment. It is a modified form of older tetracycline at C-9 aminomethyl substituent of 6-member core ring of tetracycline. Modification form shows its activity against efflux pump and ribosomal protein protection mechanism of tetracycline resistance. Generally, omadacycline is effective against methicillin-resistant S. aureus (MRSA), Streptococcus pneumoniae, vancomycin-resistant Enterococcus (VRE), Legionella and Chlamydia spp. Efficacy, safety and tolerability profile of omadacycline those compares with recent antibiotics shows that omadacycline is less resistant than others. One derivative from tetracycline derivatives is 9-neopentylaminomethylminocycline called omadacycline was discovered and ongoing phase III clinical experiments as a therapy for acute bacterial skin and skin structure infections (ABSSSI) as well as community-acquired bacterial pneumonia (CABP). Omadacycline seems to be a strong drug candidate for future promising new antibacterial agent that is effective against ABSSSI and CABP.

Anemia de Diamond Blackfan: un diagnóstico de exclusión / Anemia of Diamond Blackfan: an exclusión diagnosis

La anemia de Diamond Blackfan es un trastorno genético y clínico raro, caracterizado por aplasia eritrocitaria, que clásicamente se manifiesta durante el primer año de vida, típicamente a los 2-3 meses de edad. El 25% de los afectados presentan anemia severa en la infancia, normo o macrocitosis, reticulocitopenia y disminución selectiva de células precursoras eritroides en medula ósea. Es causada por mutaciones que afectan genes que codifican para proteínas ribosomales, inicialmente fue identificado RPS19, que codifica la proteína S19 y las mutaciones a otros genes que codifican proteínas ribosomales. Se presenta el caso de una paciente de cuatro meses de edad quien debutó con anemia severa, quien no mejoró con la suplencia de hierro, vitamina B12, y ácido fólico y además fueron descartadas sistemáticamente causas frecuentes de anemia. El diagnóstico de anemia de Diamond Blackfan en nuestro medio es un diagnóstico de exclusión, dada la dificultad para acceso a pruebas de confirmación genética. Se establece el diagnóstico y se da manejo con glucocorticoides con buena respuesta clínica y paraclínica

The Diamond Blackfan anemia is a rare genetic and clinical disorder. It is characterized by red cell aplasia, which typically occurs during the first year of life, typically during the second to the third month of age. 25% of the patients had severe anemia during their childhood, normo or macrocytosis, reticulocyte and selective decrease in the number of erythroid precursor cells in bone marrow. It is caused by mutations affect genes encoding ribosomal proteins, RPS19 initially was identified, which encodes S19 protein and mutations in other genes encoding ribosomal proteins. We present a case of a four-month-old who debuted with severe anemia in whom the substitution were iron supplements, vitamin B12 and folic acid, showed no improvement and who also were systematically discarded as common causes of anemia. The diagnosis of Diamond Blackfan anemia in our country is a diagnosis of exclusion, given the difficulty of access to genetic confirmation tests. In this article the diagnosis is established and gives management with glucocorticoid with good clinical and paraclinical response

Clinical features and pathogenic gene detection of Diamond-Blackfan anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical features of Diamond-Blackfan anemia (DBA) and related pathogenic genes.</p><p><b>METHODS</b>A retrospective analysis was performed for the clinical data of two children with DBA, and related literature was reviewed.</p><p><b>RESULTS</b>The two children with DBA (2-3 months old) manifested with severe normochromic normocytic anemia, decreased reticulocyte count, and increased serum iron and serum ferritin. Normal white blood cell and platelet counts were noted in the two patients. Bone marrow examination showed a decreased percentage of erythrocytes and rare normoblasts in the two patients. Gene screening showed a reported pathogenic heterozygous mutation in RPS19 gene, c.212G>A (p. Gly71Glu), in one patient, and there were no mutations in his parents. In the other patient, gene screening showed a heterozygous mutation in RPL5 gene, c.740T>C (p. I247L), which had not been reported in literature, and there were no mutations in her parents. A bioinformatic analysis showed that this might be a pathogenic mutation.</p><p><b>CONCLUSIONS</b>The onset age of DBA is early infancy in most children, with a manifestation of erythroid deficiency. RPS19 and RPL5 gene mutations are common causes of this disease. Molecular detection helps with the early diagnosis of DBA.</p>

Differential Protein Expressions in Virus-Infected and Uninfected Trichomonas vaginalis

Protozoan viruses may influence the function and pathogenicity of the protozoa. Trichomonas vaginalis is a parasitic protozoan that could contain a double stranded RNA (dsRNA) virus, T. vaginalis virus (TVV). However, there are few reports on the properties of the virus. To further determine variations in protein expression of T. vaginalis, we detected 2 strains of T. vaginalis; the virus-infected (V⁺) and uninfected (V⁻) isolates to examine differentially expressed proteins upon TVV infection. Using a stable isotope N-terminal labeling strategy (iTRAQ) on soluble fractions to analyze proteomes, we identified 293 proteins, of which 50 were altered in V⁺ compared with V⁻ isolates. The results showed that the expression of 29 proteins was increased, and 21 proteins decreased in V⁺ isolates. These differentially expressed proteins can be classified into 4 categories: ribosomal proteins, metabolic enzymes, heat shock proteins, and putative uncharacterized proteins. Quantitative PCR was used to detect 4 metabolic processes proteins: glycogen phosphorylase, malate dehydrogenase, triosephosphate isomerase, and glucose-6-phosphate isomerase, which were differentially expressed in V⁺ and V⁻ isolates. Our findings suggest that mRNA levels of these genes were consistent with protein expression levels. This study was the first which analyzed protein expression variations upon TVV infection. These observations will provide a basis for future studies concerning the possible roles of these proteins in host-parasite interactions.

Diverse Immunoprofile of Ductal Adenocarcinoma of the Prostate with an Emphasis on the Prognostic Factors

BACKGROUND: Ductal adenocarcinoma (DAC) of the prostate is an uncommon histologic subtype whose prognostic factors and immunoprofile have not been fully defined. METHODS: To define its prognostic factors and immunoprofile, the clinicopathological features, including biochemical recurrence (BCR), of 61 cases of DAC were analyzed. Immunohistochemistry was performed on tissue microarray constructs to assess the expression of prostate cancer-related and mammalian target of rapamycin (mTOR) signaling-related proteins. RESULTS: During the median follow-up period of 19.3 months, BCR occurred in 26 cases (42.6%). DAC demonstrated a wide expression range of prostate cancer-related proteins, including nine cases (14.8%) that were totally negative for pan-cytokeratin (PanCK) immunostaining. The mTOR signaling-related proteins also showed diverse expression. On univariate analysis, BCR was associated with high preoperative serum levels of prostate-specific antigen (PSA), large tumor volume, predominant ductal component, high Gleason score (GS), comedo-necrosis, high tumor stage (pT), lymphovascular invasion, and positive surgical margin. High expressions of phospho-mTOR (p-mTOR) as well as low expressions of PSA, phospho-S6 ribosomal protein (pS6) and PanCK were associated with BCR. On multivariable analysis, GS, pT, and immunohistochemical expressions of PanCK and p-mTOR remained independent prognostic factors for BCR. CONCLUSIONS: These results suggest GS, pT, and immunohistochemical expressions of PanCK and p-mTOR as independent prognostic factors for BCR in DAC. Since DAC showed diverse expression of prostate cancer–related proteins, this should be recognized in interpreting the immunoprofile of DAC. The diverse expression of mTOR-related proteins implicates their potential utility as predictive markers for mTOR targeted therapy.

Molecular cloning and characterization of porcine ribosomal protein L21

Ribosomal protein L21 (RPL21) is a structural component of the 60S subunit of the eukaryotic ribosome. This protein has an important role in protein synthesis and the occurrence of hereditary diseases. Pig is a common laboratory model, however, to the best of our knowledge, its RPL21 gene has not been cloned to date. In this study, we cloned and identified the full-length sequence of the pig RPL21 gene for the first time. In addition, we examined its expression pattern and function by using overexpression or knockdown approaches. As a result, we obtained a 604 bp segment that contains a 483 bp open reading frame encoding 160 amino acids. The pig RPL21 gene is located in the “+” strand of chromosome 11, which spans 2167 bp from 4199792 to 4201958. Pig RPL21 protein has nine strands and two helices in its secondary structure. Pig RPL21 is predominantly expressed in ovary and lung, at lower levels in kidney, small intestine, and skin, and at the lowest levels in heart and liver. Furthermore, RPL21 expression is closely connected with cell proliferation and cell cycle arrest. The results are intended to provide useful information for the further study of pig RPL21.

Estrogen deficiency in ovariectomized rats: can resistance training re-establish angiogenesis in visceral adipose tissue?

OBJECTIVE: The purpose of this study was to investigate the effects of resistance training on angiogenesis markers of visceral adipose tissue in ovariectomized rats. METHOD: Adult Sprague-Dawley female rats were divided into four groups (n=6 per group): sham-sedentary, ovariectomized sedentary, sham-resistance training and ovariectomized resistance training. The rats were allowed to climb a 1.1-m vertical ladder with weights attached to their tails and the weights were progressively increased. Sessions were performed three times per week for 10 weeks. Visceral adipose tissue angiogenesis and morphology were analyzed by histology. VEGF-A mRNA and protein levels were analyzed by real-time PCR and ELISA, respectively. RESULTS: Ovariectomy resulted in higher body mass (p=0.0003), adipocyte hypertrophy (p=0.0003), decreased VEGF-A mRNA (p=0.0004) and protein levels (p=0.0009), and decreased micro-vascular density (p=0.0181) in the visceral adipose tissue of the rats. Resistance training for 10 weeks was not able to attenuate the reduced angiogenesis in the visceral adipose tissue of the ovariectomized rats. CONCLUSION: Our findings indicate that the resistance training program used in this study could not ameliorate low angiogenesis in the visceral adipose tissue of ovariectomized rats.

Screening of drug resistent gene by cyclical packaging rescue of hepatocellular carcinoma retroviral cDNA libraries / 生物工程学报

Multidrug resistant genes are highly expressed in hepatocellular carcinoma that seriousty affects the effect of chemotherapy. Screening of resistant genes from HCC cells and studying its mechanism of drug resistance will be helpful to improve the effecacy of chemotherapy for hepatocellular carcinoma. Here we described an alternative method called cyclical packaging rescue (CPR). First we constructed a retrovirus cDNA library of hepatoma cells and used it to infect fibroblasts. Then we added drugs to screen survival cells. The survival cells, stably integrated helper-free retroviral libraries, were recovered rapidly after transfection with plasmids expressing retroviral gag-pol and env genes. Through this method, retroviral RNAs were directly repackaged into new infectious virions. Recovered retroviral supernatant was then used to reinfect fresh target cells. When performed in concert with selection using functional assays, cDNAs regulating functional responses could be identified by enrichment through multiple rounds of retroviral library recovery and retransmission. Using CPR, we obtained several cDNAs. After a preliminary detection, we found Ribosomal protein S11 (RPS11), Ribosomal protein L6 (RPL6), Ribosomal protein L11 (RPL11), Ribosomal protein L24 (RPL24) possibly had drug resistant function.

Effect of ribosome engineering on butenyl-spinosyns synthesis of Saccharopolyspora pogona / 生物工程学报

Through introducing mutations into ribosomes by obtaining spontaneous drug resistance of microorganisms, ribosome engineering technology is an effective approach to develop mutant strains that overproduce secondary metabolites. In this study, ribosome engineering was used to improve the yield of butenyl-spinosyns produced by Saccharopolyspora pogona by screening streptomycin resistant mutants. The yields of butenyl-spinosyns were then analyzed and compared with the parent strain. Among the mutants, S13 displayed the greatest increase in the yield of butenyl-spinosyns, which was 1.79 fold higher than that in the parent strain. Further analysis of the metabolite profile of S13 by mass spectrometry lead to the discovery of Spinosyn α1, which was absent from the parent strain. DNA sequencing showed that there existed two point mutations in the conserved regions of rpsL gene which encodes ribosomal protein S12 in S13. The mutations occurred a C to A and a C to T transversion mutations occurred at nucleotide pair 314 and 320 respectively, which resulted in the mutations of Proline (105) to Gultamine and Alanine (107) to Valine. It also demonstrated that S13 exhibited genetic stability even after five passages.

Phenotypic and genetic analysis of a child with blepharophimosis, ptosis, epicanthus inverses syndrome and tetralogy of Fallot / 中华医学遗传学杂志

OBJECTIVE To determine the genetic cause of a child with blepharophimosis, ptosis, and epicanthus inverses syndrome and tetralogy of Fallot, and to correlate the phenotype with the genotype. METHODS Routine G-banding has been previously performed on the patient and her parents. Chromosome microarray analysis (CMA) was performed for the three individuals and the fetus. RESULTS Chromosomal analysis has suggested normal karyotypes for the child and her parents. However, a de novo 8.9 Mb deletion on chromosome 3q22.1-q23 was detected by CMA. The deleted region has encompassed 74 genes including 41 disease-related genes, and this is also the most frequent region involved in interstitial 3q deletion. Patients with deletion of this region often have a common feature of dysplasia of eyelids, as well as a spectrum of other anomalies according to different breakpoints, including microcephaly, skeletal anomalies, congenital heart defects, cranial anomalies, intellectual disability and developmental delay. The patient's phenotype was in accordance with such spectrum. Her parents and sib did not show this variation by CMA. CONCLUSION The de novo interstitial deletion of 3q22.1-q23 probably underlies the main clinical manifestation in this child. CMA can provide more detailed information and allow further investigation of the genotype-phenotype correlation.