Mating-Type Genes Control Sexual Reproduction, Conidial Germination, and Virulence in Cochliobolus lunatus.

Cochliobolus lunatus (anamorph: Curvularia lunata) is a major pathogenic fungus that causes the Curvularia leaf spot of maize. ClMAT1-1-1 and ClMAT1-2-1, the C. lunatus orthologs of C. heterostrophus ChMAT1-1-1 and ChMAT1-2-1, were investigated in the present study to uncover their functions in C. lunatus. Southern blot analysis showed that these mating-type MAT genes exist in the C. lunatus genome as a single copy. ClMAT1-1-1 and ClMAT1-2-1 were knocked out and complemented to generate ΔClmat1-1-1 and ΔClmat1-2-1 and ΔClmat1-1-1-C and ΔClmat1-2-1-C, respectively. The mutant strains had defective sexual development and failed to produce pseudothecia. There were no significant differences in growth rate or conidia production between the mutant and wild-type strains. However, the aerial mycelia and mycelial dry weight of ΔClmat1-1-1 and ΔClmat1-2-1 were lower than those of wild type, suggesting that MAT genes affect asexual development. ClMAT genes were involved in the responses to cell wall integrity and osmotic adaptation. ΔClmat1-2-1 had a lower conidial germination rate than the wild-type strain CX-3. The virulence of ΔClmat1-2-1 and ΔClmat1-1-1 was also reduced compared with the wild-type. Complementary strains could restore all the phenotypes.

LncRNA APPAT regulated miR-328a/Pkp1 signal pathway to participate in breast cancer.

OBJECTIVE: Recent studies indicated long non-coding RNA (lncRNA) is involved in the development of breast cancer, which is the pathological basis of breast cancer. Here, we reported the molecular mechanisms by which lncRNA APPAT regulated in the progression of breast cancer. MATERIALS AND METHODS: QPCR was used to inspect the expression of lncRNA APPAT and miR-328a in breast cancer cell lines. Luciferase reporter assay confirmed the direct target effect of APPAT and miR-328a. Western blot was used to check Pkp1 protein expression in breast cancer cell lines. RESULTS: The expressions of lncRNA APPAT, Pkp1 protein levels and miR-328a were commonly expressed in breast cancer cells. The inhibition of lncRNA APPAT expression repressed cell proliferation, migration and invasion in breast cancer and reverse results were found after lncRNA APPAT overexpressing. Mechanistically, the binding targets of lncRNA APPAT vs. miR-328a and Pkp1 vs. miR-328a were checked in breast cancer. Meanwhile, miR-328a silencing enhanced the proliferation, migration and invasion of breast cancer cells. Moreover, the effect caused by Pkp1 silencing on cell proliferation, migration and invasion was reversed by miR-328a inhibitor in MCF-7 and BT594 cells. Additionally, Pkp1 knockout reversed the effect of cell proliferation, migration and invasion triggered by APPAT elevated. Taken together, these results showed miR-328a as a downstream target of lncRNA APPAT linking lncRNA APPAT to Pkp1. CONCLUSIONS: LncRNA APPAT regulated the proliferation, migration, invasion of breast cancer by regulating miR-328a/Pkp1 signaling pathway, providing a novel possible strategy for the treatment of breast cancer.

[Analysis on the polymorphisms of human B cell epitopes of 5 specificity antigens in Mycobacterium tuberculosis in China].

OBJECTIVE: To study the diversities of human B cell epitopes of five proteins (Mpt83, Mpt70, LpqH, PstS3, GroES) in Mycobacterium tuberculosis isolates from China. METHODS: We selected 179 strains isolated from patients with tuberculosis in different regions of China, and cultured these strains by L-J medium. The gene sequences of these 5 proteins were amplified and sequenced by PCR. The variations (single nucleotide polymorphisms, SNP) of the DNA sequences were compared and analyzed according to the immune epitope database (IEDB). The synonymous mutation rate (dS), non-synonymous mutation rate (dN) and dN/dS values were calculated with MEGA6 software. RESULTS: Among the 179 clinical MTBC isolates, 7 SNP mutations were found in the mpt83gene. The dN/dS value of the whole mpt83 gene was 0.88. One SNP mutation was found in the mpt70 gene. The dN/dS values of the whole pstS3 gene and non-B epitopes areas were 1.74 and 1.40 respectively. But no mutation was found in the groES gene. CONCLUSION: The mpt83, lpqH and pstS3 genes of 179 MTBC strains contain gene SNPs and human B cell epitopes diversities, while the coding gene and human B cell epitopes of protein mpt70 and groES were conservative.

First Report of Phomopsis longicolla Causing Leaf Spot on Soybean in China.

During July 2012, leaf spots affecting 60% of the leaves were observed on soybean cultivar He Feng 60 in fields near Shenyang City, Liaoning Province, leading to 5 to 10% yield loss. The leaf spots were associated with the leaf margins and were irregularly shaped, with brown to black margins and surrounded by a thin, yellow halo. Often, several spots merged to form large necrotic areas, which contained numerous pycnidia on the underside of the leaf. Small pieces (5 mm2) were excised from the margin of diseased and healthy tissue, surface-sterilized in 70% ethanol solution for 30 s and 0.1% mercuric chloride solution for 1 min, washed in three changes of sterile distilled water, and transferred to plates containing potato dextrose agar (PDA). Cultures were maintained in an incubator at 25°C with a 12 h dark/light photoperiod for 5 to 7 days. On PDA, colonies were white with yellow areas, floccose, dense, and moderately fast growing, attaining a diameter of 3.9 mm after 5 days and 9.0 mm after 14 days. Finally, large black stromata appeared after 28 days at 25°C. The conidiomata pycnidia were black, stomatic, globose, length 83.6 to 232 µm, width 37.9 to 146.3 µm and produced α-conidia that were unicellular, hyaline, sometimes two-guttulate, length 4.75 to 8.25 µm, width 1.50 to 3.00 µm. ß-Conidia were not observed. To confirm the morphological identification, the ribosomal internal transcribed spacers (ITS1-5.8S-ITS2) from isolates were sequenced (GenBank Accession No. KC460334). The PCR products were cloned into a pMD-19T Cloning Vector (Sangon Biotech, Shanghai, China). The clones were purified with TIANprep Mini Plasmid Kit (Tiangen Biotech, Beijing, China) to get the full-length ITS sequence. BLAST analysis of the isolates showed 100% nucleotide sequence identity with Phomopsis longicolla (AY745021). Four additional primer pairs-large subunit (NL1/NL4), beta-tublin gene (Bt2a/Bt2b), translation elongation factor 1α gene(EF1-728F/EF1-986R), and act gene(ACT-512F/ACT-783R) (1,2)-were amplified and sequenced as described above. The large subunit gene, ß-tubulin gene, and translation elongation factor 1α gene from isolates were sequenced (Sangon Biotech). BLAST analysis indicated that the isolates had 100% nucleotide sequence identity with P. longicolla (AB107259, HQ333514, and AF398896). Because the act gene sequence of P. longicolla was not in the NCBI database, this sequence had 94% nucleotide sequence identity with P. cuppatea (JN230389). To fulfill Koch's postulates, five leaves on five healthy soybean plants were inoculated with a conidial suspension (106/ml). Plants inoculated with sterile water served as the noninoculated controls. Plants were incubated in the greenhouse at 25°C. All the inoculated leaves developed pinhead spots on the leaves, gradually increasing to large brown spots. Spots were irregularly shaped, brown and necrotic in the center, and surrounded by a yellow halo. Black pycnidia appeared after 10 days, whereas the noninoculated control plants remained asymptomatic. P. longicolla was consistently recovered from all inoculated plants, except the control. Morphological description of isolates was similar to that of Hobbs (3). However, as described by Hobbs and others, P. longicolla conidiomata pycnidia have prominent necks more than 200 µm long, opening by apical ostioles; locules are uniostiolate or multiostiolate, globose, up to 500 µm wide. The pycnidia size of isolates by frozen section method was smaller than that of Hobbs. Based on morphological and sequence comparisons, the pathogen of leaf spot disease is caused by P. longicolla. This is the first reported leaf spot caused by P. longicolla on soybean in China. References: (1) T. Boekhou et al. Stud. Mycol. 38:75, 1995. (2) P. W. Crous et al. Stud. Mycol. 75:37, 2013. (3) T. W. Hobbs et al. Mycologia 77:535, 1985.

Detection of differentially expressed genes in the longissimus dorsi of Northeastern Indigenous and Large White pigs.

Recent attention in pig breeding programs has focused on the improvement of pork quality in response to increasing consumer demands. Compared to the fatty-type Northeastern Indigenous (Chinese) breed of pigs, the lean-type Large White has lower intramuscular fat and inferior eating quality from the perspective of the Chinese consumer. In order to investigate the molecular basis of differences in pork quality in Chinese indigenous and Western breeds, longissimus dorsi samples were collected from three adult Northeastern Indigenous and three adult Large White pigs. The RNAs were extracted and hybridized to the porcine Affymetrix GeneChip. Microarray analysis demonstrated differential expression of 1134 genes of which 401 have a known function. One hundred and thirty-six genes were up-regulated and 998 down-regulated in Northeastern Indigenous breed compared to Large White pigs. We screened 10 genes as candidate genes associated with pork quality. We investigated a single nucleotide polymorphism in the 5' regulatory region of the gene FABP4 in 65 Songliao black swine, using PCR-single-strand conformational polymorphism. We found this polymorphism to be highly significantly associated with marbling and intra-muscular fat content (P ≤ 0.01). Genotype BB had higher marbling than AB and AA, but there was no significant difference between AB and AA. Genotype BB and AB had higher intra-muscular fat content than AA, but there was no significant difference between BB and AB. These results help to elucidate the genetic mechanisms behind differences in pork quality and provide a theoretical basis for selection and genetic improvement of meat quality traits in pigs.

Direct observation of lateral photovoltaic effect in nano-metal-films.

Lateral photovoltaic effect (LPE) observed on the metal films is unusual because it violates a principle that the LPEs are always observed on the surface of a semiconductor. Compared with early studies, we have realized an obvious metal film LPE in a metal-semiconductor (MS) structure. By further arguing with experimental results, this work also intensively elucidates many features of LPE which the early models never touched upon. All the data and analyses in this study indicate that metal side LPE in MS structure has some natural superiorities to the semiconductor side LPE and may open many exciting opportunities for realizing multifunctional devices.

The Co-film-thickness dependent lateral photoeffect in Co-SiO2-Si metal-oxide-semiconductor structures.

We report a transient lateral photoeffect (LPE) in thin metallic Co films deposited on n-type Si substrates with native SiO(2) surfaces. Under the nonuniform irradiation of a laser beam, the lateral phtovoltage (LPV) shows high sensitivity to the laser position in the metal film plane. This effect can be interpreted by the metal-semiconductor (MS) junction formed between metal and semiconductor. The LPV depends significantly on the thickness of Co film. The position sensitivity shows a peak value of 42.6 mV/mm for Co(2.8mn)-SiO(2)-Si and decreases greatly with the increase of the Co film thickness. We explain that by the shorting effect of the metallic film.

Electron microscopy observations on the role of twinning in the evolution of microstructures.

Twinning plays an important role in phase transformations and can have significant effects on microstructural evolution. Different roles of twinning in the development of microstructures during precipitation and phase transformations are reviewed and illustrated with examples from investigations by high-resolution electron microscopy, including the effect of multiple twinning on the development of Ge precipitates in Al-Ge and Ag-Ge alloys, the twin dissociation of grain boundaries in Au, the formation of hexagonal Si at twin intersections and the effect of twin boundaries on the equilibrium shape of Pb inclusions in Al.

Increased chromosomal radiosensitivity in patients undergoing radioimmunoglobulin therapy.

Lymphocytes from individual patients undergoing radiolabeled immunoglobulin therapy have been examined both for chromosome aberrations expressed immediately upon explant, or for chromosome aberrations induced by a subsequent challenge of gamma-rays after PHA-stimulated proliferation. Despite interpatient variation, there is strong correlation between levels of chromosome aberrations observed in the initial mitosis after mitogenic stimulation and levels induced by a challenge dose of radiation in replicate cultures after several cell cycles of growth. These data indicated that even after proliferation, human lymphocytes retain a memory of in vivo exposure to ionizing radiation that can be observed by challenge with a clastogenic agent. This persistent hypersensitivity occurs at high frequency, suggesting that it may be related to initial steps in multistage carcinogenesis.