Molecular phylogeny,pathogenic variability and phytohormone production of Fusarium species associated with bakanae disease of rice in temperate agro-ecosystems

Molecular Biology Reports - Bakanae is the emerging disease threating the rice cultivation globally. Yield reduction of 4–70% is recorded in different parts of the world. A total of 119...     

Taurine Upregulates miRNA-122-5p Expression and Suppresses the Metabolizing Enzymes of Glycolytic Pathway in Hepatocellular Carcinoma

Molecular Biology Reports - Hepatocellular carcinoma (HCC) is a complicated disease with a poor prognosis and high mortality rates. The prevention, control, diagnosis, and treatment of liver cancer...     

Standardization of seed storage conditions in chilgoza pine (Pinus gerardiana Wall.): an endangered pine of Hind Kush Himalaya

The seeds of chilgoza pine (Pinus gerardiana) show moderate germination and not retain better germinability under normal ambient storage. In the present study, five storage containers [polythene bags (C₁), plastic jars (C₂), canvas bags (C₃), earthen pots (C₄) and tin boxes (C₅)] and four temperature regimes (19–22 °C) (room temperature, T₁), 0 ± 1 °C (T₂), ?4 ± 1 °C (T₃) and 4 ± 1 °C (T₄) were tested and the suitable seed storage conditions of chilgoza pine to retain viability were standardized. The storage devices preserve and retain viability trend of C₄ > C₃ > C₁ > C₂ > C₅ and T₂ > T₃ > T₄ > T₁ in the species throughout the storage period. However, the interaction treatment (C₄T₂) of earthen pots under 0 ± 1 °C temperature regime maintained significantly (P < 0.05) maximum germinability after 9 months (58.3 %) followed by C₃T₂ and C₄T₃ (47.5 %) as compared to other storage conditions. Notably, a sharp decline in germinability was recorded in seeds stored in tin boxes placed at room temperature. The implementation of these results for conservation management, especially nursery development and sustainable utilization of P. gerardiana in Himalayan region, has been suggested.     

Cell type-dependent internalization of the Escherichia coli STb enterotoxin

Previous studies have suggested that internalization of the Escherichia coli STb enterotoxin in human and rat intestinal epithelial cells is involved in STb pathogenesis, but toxin uptake in porcine jejunum epithelium, the in vivo target tissue, still remains elusive. Using flow cytometry, we studied the internalization of fluorescein isothiocyanate-labelled STb in porcine intestinal epithelial IPEC-J2 and murine fibroblast NIH-3T3 cell lines. In contrast to the selective pronase resistance of STb in NIH-3T3 cells at 37 °C, but not at 4 °C, indicative of toxin internalization, most of the toxin was pronase-sensitive at both temperatures in IPEC-J2 cells, indicating reduced uptake, but significant cell surface binding. Actin reorganization is required for STb internalization by NIH-3T3 cells, confirming STb endocytosis in these cells. The toxin receptor, sulfatide, could not explain these internalization differences because both cell lines possessed surface sulfatide and internalized antisulfatide antibodies over time at 37 °C. Inhibition of lipid rafts endocytosis, known to contain sulfatide, with methyl-β-cyclodextrin or genistein, did not influence toxin uptake by either cell line. STb internalization is therefore differentially regulated depending on the cell type, possibly by factors other than sulfatide. Although a small STb fraction could be internalized by porcine intestinal epithelial cells, our findings suggest the ability of STb to induce, from the cell surface, intracellular signalling leading to fluid secretion in porcine intestinal epithelium.     

Synaptojanin 2 functions at an early step of clathrin-mediated endocytosis

Synaptojanin 2 is a ubiquitously expressed polyphosphoinositide phosphatase that displays a high degree of homology in its catalytic domains with synaptojanin 1 [1,2]. Neurons of synaptojanin 1-deficient mice display an increase in clathrin-coated vesicles and delayed reentry of recycling vesicles into the fusion-competent vesicle pool, but no defects in early steps of endocytosis [3,4]. Here we show that inhibition of synaptojanin 2 expression via small interfering (si) RNA causes a strong defect in clathrin-mediated receptor internalization in a lung carcinoma cell line. This inhibitory phenotype is rescued by overexpression of wild-type synaptojanin 2, but not of wild-type synaptojanin 1 or mutant synaptojanin 2 that is deficient in 5'-phosphatase activity. In addition, electron-microscopic analysis shows that synaptojanin 2 depletion causes a decrease in clathrin-coated pits and vesicles. These results suggest a role for synaptojanin 2 in clathrin-coated pit formation and imply that lipid hydrolysis is required at an early stage of clathrin-mediated endocytosis. Taken together, our results also indicate that synaptojanin 2 is functionally distinct from synaptojanin 1.     

Generation of a mouse model for studying the role of upregulated RTEL1 activity in tumorigenesis

Regulator of telomere length 1 (RTEL1) is a DNA helicase protein that has been demonstrated to be required for the maintenance of telomere length and genomic stability. It has also been found to be essential for DNA homologous recombination during DNA repairing. Human RTEL1 genomic locus (20q13.3) is frequently amplified in multiple types of human cancers, including hepatocellular carcinoma and gastrointestinal tract tumors, indicating that upregulated RTEL1 activity could be important for tumorigenesis. In this study, we have developed a conditional transgenic mouse model that overexpress mouse Rtel1 in a Cre-excision manner. By crossing with a ubiquitous Cre mouse line, we further demonstrated that these established Rtel1 conditional transgenic mice allow to efficiently and highly express a functional Rtel1 that is able to rescue the embryonic defects of Rtel1 null mouse allele. Furthermore, we demonstrated that more than 70% transgenic mice that widely overexpress Rtel1 developed liver tumors that recapitulate many malignant features of human hepatocellular carcinoma (HCC). Our work not only generated a valuable mouse model for determining the role of RTEL1 in the development of cancers, but also provided the first genetic evidence to support that amplification of RTEL1, as observed in several types of human cancers, is tumorigenic.     

The Gp78 ubiquitin ligase: probing endoplasmic reticulum complexity

The endoplasmic reticulum (ER) has been classically divided, based on electron microscopy analysis, into parallel ribosome-studded rough ER sheets and a tubular smooth ER network. Recent studies have identified molecular constituents of the ER, the reticulons and DP1, that drive ER tubule formation and whose expression determines expression of ER sheets and tubules and thereby rough and smooth ER. However, segregation of the ER into only two domains remains simplistic and multiple functionally distinct ER domains necessarily exist. In this review, we will discuss the sub-organization of the ER in different domains focusing on the localization and role of the gp78 ubiquitin ligase in the mitochondria-associated smooth ER and on the evidence for a quality control ERAD domain.     

Prorenin has high affinity multiple binding sites for (pro)renin receptor

An important role of the decoy peptide sequence has recently been suggested in vitro for the binding of prorenin to the (pro)renin receptor [(P)RR]. In this study, other prospective crucial regions in renin and prorenin responsible for their interaction with (P)RR were investigated using various kinds of peptides, e.g., the “hinge” S¹⁴⁹QGVLKEDVF¹⁵⁸ designed from the structure of renin also common to prorenin, L^1PPTDTTTF^8P, L^1PPTDTTTFKRIFLKR^15P and the decoy (R^10PIFLKRMPSI^19P) designed from the predicted structure of prorenin. For the kinetic analysis, the recombinant h(P)RR was immobilized on the biosensor surface through a specific anti-(P)RR antibody. In case of the equilibrium state analysis, the (P)RR was directly adsorbed on plastic wells for observing the bindings of renin/prorenin. The dissociation constants (K_D) for the bindings of renin and prorenin to the pre-adsorbed receptors were 4.5 and 1.0 nM, respectively, similar to those stated in the kinetic study by BIAcore assay. The “hinge” region peptide bound to (P)RR in a dose-dependent manner with a K_D estimated 17.0 nM which was five times higher than that of the decoy. The K_D values for L^1PPTDTTTF^8P and L^1PPTDTTTFKRIFLKR^15P were 52 and 7.6 nM, respectively. The “hinge” peptide, as the decoy, inhibited the bindings of renin and prorenin to (P)RR. The inhibition constant (K_i) for the binding of renin and prorenin by the decoy and “hinge” were 16.7 and 15.1, and 37.1 and 30.7 nM, respectively. These in vitro studies suggest that renin has a single and prorenin has at least two high affinity binding sites for the (P)RR.     

Nitric oxide function in plant abiotic stress

Abiotic stress is one of the main threats affecting crop growth and production. An understanding of the molecular mechanisms that underpin plant responses against environmental insults will be crucial to help guide the rational design of crop plants to counter these challenges. A key feature during abiotic stress is the production of nitric oxide (NO), an important concentration dependent, redox‐related signalling molecule. NO can directly or indirectly interact with a wide range of targets leading to the modulation of protein function and the reprogramming of gene expression. The transfer of NO bioactivity can occur through a variety of potential mechanisms but chief among these is S‐nitrosylation, a prototypic, redox‐based, post‐translational modification. However, little is known about this pivotal molecular amendment in the regulation of abiotic stress signalling. Here, we describe the emerging knowledge concerning the function of NO and S‐nitrosylation during plant responses to abiotic stress.