Congenital pure red cell aplasia, also known as Diamond-Blackfan anemia (DBA), is a hereditary disease characterized by pure red cell aplasia and congenital malformation. Its main clinical features are anemia, dysplasia, and tumor susceptibility. Ribosomal protein (RP) gene mutation is the main pathogenesis of DBA. The most common type of gene mutation is RPS19 gene mutation. Heterozygous mutations in as many as 19 RP genes and other non-RP genes mutations have been identified in DBA. This review summarized briedfly the latest research advances in the pathogenesis of DBA.
Anemia, Diamond-Blackfan ; Humans ; Mutation ; Ribosomes

Carrimycin (CAM) is a new antibiotics with isovalerylspiramycins (ISP) as its major components. It is produced by Streptomyces spiramyceticus integrated with a heterogenous 4″-O-isovaleryltransferase gene (ist). However, the present CAM producing strain carries two resistant gene markers, which makes it difficult for further genetic manipulation. In addition, isovalerylation of spiramycin (SP) could be of low efficiency as the ist gene is located far from the SP biosynthesis gene cluster. In this study, ist and its positive regulatory gene acyB2 were inserted into the downstream of orf54 gene neighboring to SP biosynthetic gene cluster in Streptomyces spiramyceticus 1941 by using the CRISPR-Cas9 technique. Two new markerless CAM producing strains, 54IA-1 and 54IA-2, were obtained from the homologous recombination and plasmid drop-out. Interestingly, the yield of ISP in strain 54IA-2 was much higher than that in strain 54IA-1. Quantitative real-time PCR assay showed that the ist, acyB2 and some genes associated with SP biosynthesis exhibited higher expression levels in strain 54IA-2. Subsequently, strain 54IA-2 was subjected to rifampicin (RFP) resistance selection for obtaining high-yield CAM mutants by ribosome engineering. The yield of ISP in mutants resistant to 40 μg/mL RFP increased significantly, with the highest up to 842.9 μg/mL, which was about 6 times higher than that of strain 54IA-2. Analysis of the sequences of the rpoB gene of these 7 mutants revealed that the serine at position 576 was mutated to alanine existed in each sequenced mutant. Among the mutants carrying other missense mutations, strain RFP40-6-8 which carries a mutation of glutamine (424) to leucine showed the highest yield of ISP. In conclusion, two markerless novel CAM producing strains, 54IA-1 and 54IA-2, were successfully developed by using CRISPR-Cas9 technique. Furthermore, a novel CAM high-yielding strain RFP40-6-8 was obtained through ribosome engineering. This study thus demonstrated a useful combinatory approach for improving the production of CAM.
CRISPR-Cas Systems/genetics* ; Genetic Engineering ; Ribosomes ; Spiramycin ; Streptomyces/genetics*

BACKGROUND: Trichomonas vaginalis is a pathogenic protozoa infecting human genitourinary tract. Metronidazole is currently the drug of choice to treat T. vaginalis infection. However, because of the side effects and the occurrence of resistant strains of metronidazole, it is needed to investigate alternatives. METHODS: The antiprotozoal effect of aquatic extract from Sophora flavescens on the growth and fine structure of T. vaginalis was examined by using trypan blue exclusion assay and electron microscopy. RESULTS: One hour after the addition of 4 mg/mL extract and half hour after the addition of 5 mg/mL showed antiprotozoal effect. One to two hours after the addition of 3 mg/mL extract, the movement of flagella and axostyle had disappeared, but death of the cells had not occurred until two hours after the addition. The fine structure of the cytoplasm was also changed half an hour to two hours after addition. The number of polyribosome decreased when that of single ribosomes in the cytoplasm increased. CONCLUSION: These results indicated that S. flavescens had the antiprotozoal effect on T. vaginalis by inhibition of cell multiplication as well as an impairment of protein synthesis.
Cell Proliferation ; Cytoplasm ; Flagella ; Humans ; Metronidazole ; Microscopy, Electron ; Polyribosomes ; Ribosomes ; Sophora* ; Trichomonas vaginalis* ; Trichomonas* ; Trypan Blue

We investigated the biochemiesl change of keratin by the methods of SDS-PAGE and Two-dimensional gel electrophoresis, and observed electron microscopic ultrestructural changes in five Unna-Thost palmoplantar keratoderma patients and two normal adults. The results are summarized as follows : 1. The increased bands of 51 kd and newly appearing 48 kd, 56 kd keratins were observed on the SDS-PAGE and compared to the normsl control. 2. The newly appearing 48 kd(acidic) paired with 56 kd(basic) keratins and 51 kd keratin and the disappearance of 59 kd(basic), 64 kd(basic) keratins were observed on the two-dimensional gel electrophoresis and compared to the normal control. 3. The variable sized, numerous, globular, irregularly beam-shaped and granular kerstohyaline granules were scattered in the granular cell and corneocyte. Numerous ribosomes were noted between the clumped tonofibrils and around the keratohyaline granules. The lipid droplets were seen in the corneocytes and granular cells on the electron microscope.
Adult ; Electrophoresis, Gel, Two-Dimensional ; Electrophoresis, Polyacrylamide Gel ; Humans ; Keratoderma, Palmoplantar* ; Ribosomes

Lentiviruses can infect mitotic and non-dividing cells owing to the karyophilic properties of their pre-integrating complex, which allow its active import through the nucleopore. Thus lentiviral vectors derived from human immunodeficiency virus type 1 can mediate an efficient transfer integration, and stable expression of transgenes into proliferating and stationary cells both in vivo and in vitro. By adopting the internal ribosome entry site of encephalomyocarditis virus for bicistronic expression or two promoters of EF-1alpha and SV40 for separate expression of two genes of interest, we developed two lentiviral vectors that express two genes. On FACS analysis, RT-PCR, and immunofluorescence assay, it was shown that the target cells expressed two genes of interest at different levels as the transducing vectors designed for. This vector system is useful especially for a stable, dual-gene expression and two transgene deliveries to non-dividing cells.
Encephalomyocarditis virus ; Fluorescent Antibody Technique ; HIV-1 ; Lentivirus ; Peptide Elongation Factor 1 ; Ribosomes ; Transgenes*

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.
Genetic Engineering ; Macrolides ; metabolism ; Point Mutation ; Ribosomal Proteins ; genetics ; Ribosomes ; metabolism ; Saccharopolyspora ; metabolism

BACKGROUND AND PURPOSE: The detection of aquaporin 4-IgG (AQP4-IgG) is now a critical diagnostic criterion for neuromyelitis optica spectrum disorder (NMOSD). To evaluate the serostatus of NMOSD patients based on the 2015 new diagnostic criteria using a new in-house cell-based assay (CBA). METHODS: We generated a stable cell line using internal ribosome entry site-containing bicistronic vectors, which allow the simultaneous expression of two proteins (AQP4 and green fluorescent protein) separately from the same RNA transcript. We performed in-house CBA using serum from 386 patients: 178 NMOSD patients diagnosed according to the new diagnostic criteria without AQP4-IgG, 63 high risk NMOSD patients presenting 1 of the 6 core clinical characteristics of NMOSD but not fulfilling dissemination in space, and 145 patients with other neurological diseases, including 66 with multiple sclerosis. The serostatus of 111 definite and high risk NMOSD patients were also tested using a commercial CBA kit with identical serum to evaluate the correlation between the 2 methods. All assays were performed by two independent and blinded investigators. RESULTS: Our in-house assay yielded a specificity of 100% and sensitivities of 80% (142 of 178) and 76% (48 of 63) when detecting definite- and high risk NMOSD patients, respectively. The comparison with the commercial CBA kit revealed a correlation for 102 of the 111 patients: no correlation was present in 7 patients who were seronegative using the commercial method but seropositive using the in-house method, and in 2 patients who were seropositive using the commercial method but seronegative using the in-house method. CONCLUSIONS: These results demonstrate that our in-house CBA is a highly specific and sensitive method for detecting AQP4-IgG in NMOSD patients.
Aquaporin 4 ; Cell Line ; Humans ; Methods ; Multiple Sclerosis ; Neuromyelitis Optica* ; Research Personnel ; Ribosomes ; RNA ; Sensitivity and Specificity

ITSI-5.8S-ITSII rDNA region was amplified from the reference strains and clinical isolates with ITS1 and ITS4 primers. These primers amplified DNA fragments of 550 bp in Microsporum audouinii and Trichophyton violaceum, 700 bp in Microsporum gypseum, Trichophyton mentagrophytes, Trichophyton rubrum, and Trichophyton tonsurans, and 750 bp in Microsporum ferreugineum and Microsporum canis. The restriction enzyme patterns of PCR products digested with 13 restriction enzyme including PstI were distint among the genera, whereas identical in the same species. Examination of the ITS (Internal Transcribed Spacers)1 nucleotide sequence revealed that there was the genetic difference in each genera and species. Phylogenetic relationship among each species showed that the Trichophyton mentagrophytes was more closely related Trichophyton tonsurans than Trichophyton rubrum, and Microsporum gypseum was less related than Microsporum spp.
Arthrodermataceae* ; Base Sequence* ; DNA* ; DNA, Ribosomal ; Microsporum ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length* ; Ribosomes* ; Trichophyton

Aminoglycosides are one of the clinically relevant antibiotics. They kill bacteria by binding to bacterial 30S subunit of ribosome. Resistance to aminoglycosides occurs by three different mechanisms: 1. Production of an enzyme that modifies aminoglycosides, 2. Impaired entry of aminoglycoside into the cell by altering the OMP permeability, decreasing inner membrane transport, or active efflux, 3. The receptor protein on the 30S ribosomal subunit may be deleted or altered as a result of a mutation. By far, enzymatic modification has been the most important mechanism. In this review, the mechanisms of action and resistance, and the prevalence of resistance due to acquisition of enzymes are briefly described.
Aminoglycosides ; Anti-Bacterial Agents ; Bacteria ; Membranes ; Permeability ; Prevalence ; Ribosome Subunits ; Ribosomes

Morphological studies have an important role in establishing the timing of irreversible damage occurred in cryptorchid testis. The present study was undertaken to determine how soon definitive sign or testis pathology may appear in cyptorchid testis. Testicular biopsies were collected at the time of orchiopexy from 79 patients during the period from January, 1988 to June, 1990, and then we examined ultrastructural changes of cryptorchid testis with light and electron microscopy. Comparing with normal testis, following results were obtained ; l. The volume of cryptorchid testis became smaller than normal after age of 14. 2. Mean tubular diameter became smaller after age of 14 and basement membrane thickened prominently after age of 20. 3. The increase number of mitochondria appeared at age of 2 4. Cytoplasmic vacuolization became prominent after age of 6, but detachment and loss of ribosome appeared at age of 20. 5. Tunica propria showed marked thickening and collagenous degeneration after age of 14. With above results, we suggest that orchiopexy should be done before age of 2.
Basement Membrane ; Biopsy ; Collagen ; Cytoplasm ; Humans ; Microscopy, Electron ; Mitochondria ; Orchiopexy ; Pathology ; Ribosomes ; Testis*