Early and late replicative chromosomal banding patterns of Gallus domesticus.

Early and late replicating chromosomal banding patterns of Gallus domesticus were investigated by cell synchronization and incorporation of 5'-bromodeoxyuridine during early and late DNA synthesis. The early replicating chromosomal banding patterns observed, as revealed by either acridine orange or Hoechst 33258/propidium iodide staining, were similar to the structural G-banding patterns obtained by trypsin digestion and Giemsa staining. Late replicating chromosomal banding showed extensive reverse band complementarity to the G-banding pattern. Cell synchronization increased the number of prometaphase and metaphase plates available for analysis. G-banding obtained by Hoechst 33258/propidium iodide staining was investigated due to the fact that it is compatible with chromosomal in situ hybridization procedures that use nonisotopically-labeled DNA probes. Standard replicative G-banded and R-banded idiograms, as obtained after cell synchronization, are proposed.     

An infrared probe of iro n porphyrin oxidation state and axial ligation.

Carbonyl stretching frequencies of acyl groups conjugated with porphyrin rings are useful probes of the effective electronegativities of corrdinated iron atoms in iron porphyrins. Acetyl carbonyl stretching frequencies for 2,4-diacetyldeuteroporphyrin IX dimethyl ester derivatives exhibit both metal oxidation state and axial ligand effects. Infrared spectra of chloroform and pyridine solutions, corrected for solvation, showed the sequences of acetyl carbonyl stretching frequencies: dipyridine iron(II) less than mu-oxo bisiron(III) less than bromo iron(III) approximately equal to chloro iron(III) and dipyridine nickel(II) less than nickel(II). Applications of the probe to the study of hemeproteins are indicated.     

Adaptive Admixture of HLA Class I Allotypes Enhanced Genetically Determined Strength of Natural Killer Cells in East Asians

Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections.     

A disintegrin and metalloproteinase 8 induced epithelial‐mesenchymal transition to promote the invasion of colon cancer cells via TGF‐β/Smad2/3 signalling pathway

A disintegrin and metalloproteinase 8 (ADAM8) protein is a multi‐domain transmembrane glycoprotein which involves in extracellular matrix remodelling, cell adhesion, invasion and migration. ADAM8 and epithelial‐mesenchymal transition (EMT) play an important role in tumour invasion has been well established. However, the interaction between ADAM8 and EMT has remained unclear. The data of colon cancer patients obtained from TCGA (The Cancer Genome Atlas) and GTEx (Genotype‐Tissue Expression Project) were analysed by the bioinformatics research method. The expression of ADAM8 in colon cancer cells was up‐regulated and down‐regulated by transfecting with the expression plasmid and small interfering RNA, respectively. Transwell invasion assay, immunohistochemistry, immunocytochemistry, Western blotting and qRT‐PCR were utilized to study the effect of ADAM8 on colon cancer cell''s EMT and its related mechanisms. Analysis of TCGA and GTEx data revealed that ADAM8 was linked to poor overall survival in colon cancer patients. Besides, ADAM8 was correlated with multiple EMT biomarkers (E‐cadherin, N‐cadherin, Vimentin, Snail2 and ZEB2). In vitro, we also proved that the up‐regulation of ADAM8 could promote EMT effect and enhance the invasive ability of colon cancer cells. On the contrary, the down‐regulation of ADAM8 in colon cancer cells attenuated these effects above. Further studies suggested that ADAM8 modulated EMT on colon cancer cells through TGF‐β/Smad2/3 signalling pathway. Our research suggested that ADAM8 could be a potential biomarker for the prognosis of colon cancer and induced EMT to promote the invasion of colon cancer cells via activating TGF‐β/Smad2/3 signalling pathway.     

Neobavaisoflavone inhibits osteoclastogenesis through blocking RANKL signalling‐mediated TRAF6 and c‐Src recruitment and NF‐κB,MAPK and Akt pathways

Psoralea corylifolia (P corylifolia) has been popularly applied in traditional Chinese medicine decoction for treating osteoporosis and promoting fracture healing since centuries ago. However, the bioactive natural components remain unknown. In this study, applying comprehensive two‐dimensional cell membrane chromatographic/C18 column/time‐of‐flight mass spectrometry (2D CMC/C18 column/TOFMS) system, neobavaisoflavone (NBIF), for the first time, was identified for the bioaffinity with RAW 264.7 cells membranes from the extracts of P corylifolia. Here, we revealed that NBIF inhibited RANKL‐mediated osteoclastogenesis in bone marrow monocytes (BMMCs) and RAW264.7 cells dose dependently at the early stage. Moreover, NBIF inhibited osteoclasts function demonstrated by actin ring formation assay and pit‐formation assay. With regard to the underlying molecular mechanism, co‐immunoprecipitation showed that both the interactions of RANK with TRAF6 and with c‐Src were disrupted. In addition, NBIF inhibited the phosphorylation of P50, P65, IκB in NF‐κB pathway, ERK, JNK, P38 in MAPKs pathway, AKT in Akt pathway, accompanied with a blockade of calcium oscillation and inactivation of nuclear translocation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1). In vivo, NBIF inhibited osteoclastogenesis, promoted osteogenesis and ameliorated bone loss in ovariectomized mice. In summary, P corylifolia‐derived NBIF inhibited RANKL‐mediated osteoclastogenesis by suppressing the recruitment of TRAF6 and c‐Src to RANK, inactivating NF‐κB, MAPKs, and Akt signalling pathways and inhibiting calcium oscillation and NFATc1 translocation. NBIF might serve as a promising candidate for the treatment of osteoclast‐associated osteopenic diseases.     

DJ‐1 inhibits autophagy activity of prostate cancer cells by repressing JNK–Bcl2–Beclin1 signaling

The regulation of DJ‐1 on AR signaling plays an important role in the pathogenesis of prostate cancer (PCa). DJ‐1 could alter autophagy and regulate Beclin1‐involved autophagy response through JNK‐dependent pathway. JNK is known to mediate autophagy through Bcl2–Beclin1 complex. Therefore, this study aimed to investigate the significance of autophagy in DJ‐1‐modulated PCa cells. The current studies showed that DJ‐1 overexpression in LNCaP decreased LC3 transformation and autophagosome formation. However, DJ‐1 knockdown exerted the opposite effect. Moreover, DJ‐1 silencing inhibited survival and promoted death in LNCaP, which was recovered by autophagy inhibition with 3‐MA. In addition, DJ‐1 overexpression inhibited the phosphorylation of JNK and Bcl2, and the dissociation of Beclin1 and Bcl2; while the effect of silencing DJ‐1 was completely opposite. More important, JNK activated by anisimycin inhibited the proliferation and promoted death of DJ‐1‐overexpressed LNCaP while increasing LC3 transformation and LC3‐puncta formation, but these results were reversed by the decrease of Beclin1 (by spautin‐1). In contrast, when DJ‐1 was silenced, the death of LNCaP, LC3 transformation, and LC3‐puncta formation were inhibited by JNK inhibitor SP600125, which promoted cell proliferation. However, Bcl2 inhibition (by ABT737) reversed all the effects of SP600125. Our results suggested that DJ‐1 in PCa cells could promote the growth of PCa through autophagy inhibition, and JNK–Bcl2–Beclin1 signaling played an important role in it. The study provided new insights into the role of DJ‐1 in the development of PCa.     

Phenotypic and genetic dissection of cadmium accumulation in roots,nodes and grains of rice hybrids

Plant and Soil - Rice accumulates higher levels of cadmium (Cd) in grain than other cereals, and hybrid rice varieties cover around half of the total rice area in China. Therefore, understanding...