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Hepatitis B virus (HBV) infection is one of the most serious public health problems. HBV infection could lead to hepatitis B, and even further develop into hepatic cirrhosis and hepatocellular carcinoma. Interferon lambda (IFN-λ) is a member of the interferon (IFN) family and an important cytokine for antiviral defense. There are four members in IFN-λ family, including IFN-λ1, IFN-λ2, IFN-λ3, and IFN-λ4. The genetic polymorphisms in the IFN-λ genes are associated with HBV replication and treatment response of HBV patients. In this review, we summarized the roles of genetic polymorphisms of the IFN-λ genes played in HBV infection, disease progression and treatment, with the aim to better understand their function. This review could serve as a reference for the HBV prevention and treatment of HBV patients, as well as for future clinical usage.

Wheat is one of the most important food crops in China and worldwide. Wheat production is facing the stresses of different diseases including Fusarium head blight (FHB) which is more and more serious recently and leading to highly concerns. Unremitting efforts have been made on Fusarium head blight resistance breeding and comprehensive control technology development. Rapid progress has been achieved on discovering of resistant genetic resources, mapping of resistant QTL/genes, resistant QTL/genes cloning, gene functional research and molecular breeding. In this review, we summarize the current status of the research against FHB in wheat and discuss the issues of FHB resistance investigation to date. We also suggest emphasizing on gene cloning, developing more powerful functional markers, using haplotype-assisted selection (HAS) and marker-set-assisted selection (MSAS) for further deep FHB resistance study and breeding.

Hepatitis C virus (HCV) is the etiological factor for Hepatitis C, which is one of the most important pathogenic factors of chronic liver diseases, cirrhosis and even hepatocellular carcinoma. HCV infection brings great threat to human health. Host genetic background could impact HCV infection, viral clearance, and treatment. Recently, some genome-wide association studies (GWAS) of HCV patients were performed. The results showed that single nucleotide polymorphisms (SNPs) of the IL28B gene, which encodes protein IFN-lambda3, are associated with viral clearance and treatment effectiveness of HCV patients who were cured by PEG-IFNalpha combined with ribavirin (RBV). IFN-lambda3 interacts with its acceptor, a heterodimer (IFN-lambdaR1 x IL-10R2), and upregulates the IFN-stimulated gene factors (ISGF). IFN-lambda3 plays roles in antiviral, antitumor, and immunoloregulation, and thus it might become a potential drug for Hepatitis C treatment. However, the mechanism of the IL28B gene in HCV infection and treatment is unclear, and further studies are needed to reveal the veils and provide theoretical basis for developing a new antiviral drug in clinic.

Leber hereditary optic neuropathy (LHON; MIM 535000) is one of the most common mitochondrial diseases, with a clinical manifestation of painless, acute or sub-acute bilateral visual loss in young adults leading to blindness and central scotoma. Over 95% of LHON patients were caused by one of three primary mtDNA mutations (m.11778G>A, m.3460G>A and m.14484T>C). Incomplete penetrance and gender bias are two riddles of this disease. Here we summarized recent research progress of LHON, with a focus on the molecular pathogenic mechanisms, clinical features, in vitro experiments and animal models, and prevention and treatment of LHON. In particular, we presented the main findings and challenges in our recent efforts to decipher genetic susceptibility and mechanism of LHON in Chinese patients.

After removing gliadin and other proteins with 7.5% 2-propanol and 0.3 mol/L NaI, the total glutenin subunits were extracted with two kinds of buffer, one containing 25% 2-propanol, 0.04 mol/L Tris-HCI (pH=8.0), 10% SDS and 2% DDT and the other containing 25% 2-propanol, 0.04 mol/L Tris-HCI (pH=8.0), 10% SDS and 1.4% VP. In SDS-PAGE electrophoresis (4% stacking gel and 13% resolving ge1) system HMW-GS and LMW-GS were clearly separated by the improved method with only a single step. The background of the SDS-PAGE gel was gliadin-free. It was more effective and applicable to separate and distinguish the complex LMW-GS. This method will be used in wheat protein separation, variety identification and improvement.

Rice blast caused by Magnaporthe grisea is one of the most serious constraints on high productivity. Understanding the mechanism of the infection of Magnaporthe grisea and the change of gene expression after infection is useful to control blast disease in rice. This work presents the isolation of differentially expressed cDNA fragments from rice leaf induced by the inoculum suspension of Magnaporthe grisea using mRNA differential display technique. Total 87 differential expressed cDNA fragments were recoveried and reamplified. The dot-blotting results showed that 6 fragments of 81 were confirmed to be the expression induced by Magnaporthe grisea inoculum. Those fragments were then cloned into vectors for sequencing. Sequence analysis through Internet Blast searching showed that 3 fragments were novel gene fragments. One was homologous with a putative malate synthase gene on rice chromosome 4 with 78% identities of amino acid; one was highly homologous (75% identity) with rice RPR1 gene on chromosome 11, which has a conservative structure of NBS-LRR domain and may be related to signal transduction of rice defense reaction;another one was homologous with a putative thioredoxin gene on rice chromosome 6 with the identity of 72%.

The photoperiod-temperature sensitive genic male sterile (PTSGMS) line in wheat is important for the utilization of heterosis. The wheat line, BAU3338, is an excellent PTSGMS material identified in the recent years. In this study, its PTSGMS genes were mapped using molecular markers, SSR and ISSR. The result of molecular analysis showed that the two PTSGMS loci were identified and designated as ptms1 and ptms2, respectively. In addition, the genetic effect analysis indicated that the locus effect of ptms1 was 2-3 times larger than that of ptms2.

Plant growth and development, plant cell signaling and gene regulation, plant genome research were the hotpoint of current plant biology research. We introduce the mainly foreign website concerning with the three fields, and hope it will be helpful for the plant biology researchers.

mRNA differential display with G-box family primer was used to analyze the differential expression of genes of the photoperiod-temperature sensitive genic male sterile(PTSGMS) line of wheat, BAU3338, between the sterile and fertile conditions. The result indicated that gene expression was significantly different between the two types of condition during the fertility transformation phase. The twelve qualitatively different DNA bands were identified with reverse Northern blot hybridization and five positive clones, HT1-G10, HT1-G3, HT2-G2, HT1-G4 and HT2-G5 were sequenced. The homology search indicated that HT1-G10 was highly homological (96%) to the partial sequences of Triticum aestivum chloroplast genes, rbcL and atpB, HT1-G3 was also homological (88%) to Triticum aestivum histone H2A gene and the other three gene fragments were new sequences in Gen-Bank. The analysis of the candidate gene fragments supplied some effective evidences to reveal the developmental mechanism of PTSGMS.

To detect quantitative trait loci (QTLs) controlling plant height, the plant height of 240 F2:3 lines derived from the cross of a dwarf wheat line ND3338 with a tall line F390, was assessed in field trials at two locations with three replications in 2000 and 2001. Microsatellite markers were used to construct a framework linkage map containing 215 loci with 21 linkage groups, and covering the whole genome about 3600cM. With the method of interval mapping, seven putative QTLs affecting plant height were detected on chromosomes 1B, 4B (two regions), 6A (two regions), 6D and 7A, respectively. Phenotypic variations explained by each QTL ranged from 5.2% to 50.1%, and in each environment the total putative QTLs explained about 64.8%-75% of the total phenotypic variation respectively. A major QTL located on chromosome arm 4BS near the locus Xgwm113, around the Rht-Blb locus, explained a large part of the phenotypic variation (27.8%-36.2% depending on the years or the locations). Except the QTL on chromosome 7A, all the other QTLs from ND3338 decreased the plant height, variously from 0.94 cm to 9.33 cm. Most of the identified QTLs were consistent in all the environments, and should be useful in future marker-assisted-selection programs for breeding dwarf and semi-dwarf wheat cultivars.

Immature embryos and embryo-derived calli from two cultivars of winter wheat (Triticum aestivum L.), BAU146 and BAU170, were transformed with three strains of Agrobacterium tumefaciens, AGL-1, EHA105 and LBA4404 harboring expression vector p3301 or pBTAaB. Both vectors contained bar gene and p3301 contained also gus gene with an intron. The highest explant survival rate and transformation efficiency was obtained when the bacterial cell density was OD600 1.0 with 1 h of infection incubation. Higher osmotic treatment of the explants before inoculation had a positive effect on transformation, while addition of acetosyringone showed ambiguous one, depending on the explant types and bacterium strains. The efficiencies of transformation and transgenic plant regeneration were varied greatly with the bacterium strain, receptor genotype, explant type and its age and physiological state. After optimizing these factors, a large number of PPT-resistant calli and some of PPT-resistant plants were obtained. The resistant plantlet tested and 50% to 60% of the resistant calli were GUS-positive. The integration of foreign DNA into the genome of transgenic plants (3 out 6) was further confirmed by PCR and Southern Blot analysis.

Phosphate is a major constraint to crop production, and phosphate uptake in plant is mainly by high-affinity phosphate transporter under phosphate deficiency condition. Using RT-PCR, a 1,178 bp phosphate transporter gene fragment OjPT1 was cloned from roots of Jingxi17 (Oryza sativa L. ssp. japanica) supplied with no phosphate. The comparison of this sequence with ones in GenBank indicated that it shared about 70% similarity at amino acid level with other phosphate transporters in higher plants, such as Arabidopsis thaliana, potate, tamato, Medicago truncatula and Catharanthus roseus, and high similarity with phosphate transporters in Saccharomyces cerevisiae and Neurospora crassa. RT-PCR assay showed that the OjPT1 transcripts were induced under phosphate deficiency condition. This gene fragment OjPT1 has been deposited in GenBank (accession No. AF249619).