Heterologous expression of the MiHAK14 homologue from Mangifera indica enhances plant tolerance to K+ deficiency and salinity stress in Arabidopsis

Plant Growth Regulation - As one of the most abundant ions in cells, sufficient amount of potassium (K+) is closely related to plant growth and development and contributes to plant tolerance to...     

Measuring single cardiac myocyte contractile force via moving a magnetic bead

One of the biggest problems of heart failure is the heart's inability to effectively pump blood to meet the body's demands, which may be caused by disease-induced alterations in contraction properties (such as contractile force and Young's modulus). Thus, it is very important to measure contractile properties at single cardiac myocyte level that can lay the foundation for quantitatively understanding the mechanism of heart failure and understanding molecular alterations in diseased heart cells. In this article, we report a novel single cardiac myocyte contractile force measurement technique based on moving a magnetic bead. The measuring system is mainly composed of 1), a high-power inverted microscope with video output and edge detection; and 2), a moving magnetic bead based magnetic force loading module. The main measurement procedures are as follows: 1), record maximal displacement of single cardiac myocyte during contraction; 2), attach a magnetic bead on one end of the myocyte that will move with myocyte during the contraction; 3), repeat step 1 and record contraction processes under different magnitudes of magnetic force loading by adjusting the magnetic field applied on the magnetic bead; and 4), derive the myocyte contractile force base on the maximal displacement of cell contraction and magnetic loading force. The major advantages of this unique approach are: 1), measuring the force without direct connections to the cell specimen (i.e., "remote sensing", a noninvasive/minimally invasive approach); 2), high sensitivity and large dynamic range (force measurement range: from pico Newton to micro Newton); 3), a convenient and cost-effective approach; and 4), more importantly, it can be used to study the contractile properties of heart cells under different levels of external loading forces by adjusting the magnitude of applied magnetic field, which is very important for studying disease induced alterations in contraction properties. Experimental results demonstrated the feasibility of proposed approach.     

TNF-Alpha rs1800629 Polymorphism Is Not Associated with HPV Infection or Cervical Cancer in the Chinese Population

Background

While HPV infection is the main cause of cervical cancer, genetic susceptibility to HPV infection is not well understood. Tumor necrosis factor alpha (TNF-alpha), involved in the defense against HPV infection, plays an important role in cervical cancer progression and regression. The aim of this study was to investigate the relationship between the TNF-alpha rs1800629 polymorphism and risk of HPV infection or cervical cancer.

Methods

Three groups were involved in this study of Chinese women. Group 1 consisted of 285 high risk HPV positive cervical cancer patients, Group 2, 225 high risk HPV positive patients without cervical cancer, and Group 3, 318 HPV negative women with no cervical cancer. Blood samples were obtained from all patients and genotyped by PCR-RLFP. Fifty randomly selected samples were further sequenced.

Results

The allele and genotype distributions of the TNF-alpha rs1800629 polymorphism were not significantly different between each of the groups (P>0.05). There are no significant relationship between rs1800629 polymorphism and high risk HPV infection (OR  = 0.649, 95% CI: 0.253–1.670, P = 0.371), cervical cancer (OR  = 0.993, 95% CI: 0.376–2.618, P = 0.988), or cervical cancer with HPV infection (OR  = 0.663, 95% CI: 0.250–1.758, P = 0.409).

Conclusions

We demonstrated that there is no association between TNF rs1800629 polymorphism and the HPV infection, or cervical cancer with HPV infection.     

Identification of quantitative trait loci for resistance to rice black-streaked dwarf virus disease and small brown planthopper in rice

Small brown planthopper (SBPH) and its transmitted rice black-streaked dwarf virus disease (RBSDVD) cause serious damage to rice (Oryza sativa L.) production. Though breeding of resistant cultivars is believed to be one of the most important strategies for RBSDVD management, few high-resistance lines have been found to date. In the present study, we identified an indica variety, 9194, that is highly resistant to RBSDVD and analyzed the quantitative trait loci (QTLs) underlying this resistance . In total, four QTLs for RBSDVD resistance, viz. qRBSDV3, qRBSDV6, qRBSDV9, and qRBSDV11, were identified. Among them, qRBSDV6, qRBSDV9, and qRBSDV11 with LOD (logarithm [base 10] of odds) scores of 4.42–4.48, 2.11–7.26, and 5.01–7.16 were repeatedly detected in 2 years, accounting for 10.3–16.7%, 8.3–35.5%, and 20.0–31.1% of the total phenotypic variation, respectively. Further, introgression of single- or multiple-resistance QTLs into a susceptible rice variety by marker-assisted selection (MAS) indicated that stacking the QTLs could progressively enhance RBSDVD resistance, suggesting that these QTLs act additively. The same population was also used for QTL mapping of SBPH resistance. Four QTLs, viz. qSBPH1, qSBPH5, qSBPH8, and qSBPH9, with LOD scores of 2.72, 2.78, 2.15, and 2.85 were detected, explaining 13.7%, 11.0%, 12.0%, and 21.0% of the phenotypic variation, respectively. The identification of RBSDVD and SBPH resistance QTLs, and the development of single and multiple genes with pyramided lines, in this study provides innovative resources for molecular breeding of resistant rice cultivars.     

Genome-wide association study and linkage analysis on resistance to rice black-streaked dwarf virus disease

Molecular Breeding - Wheat is one of the most important staple food crops in many parts of the world. Nitrogen (N) is often considered to be the most important mineral nutrient element for crop...