The basic helix-loop-helix-zipper domain of TFE3 mediates enhancer-promoter interaction.

Binding sites for three families of sequence-specific DNA-binding proteins, microE3, C/EBP, and OCT, are found in both the promoters and the intronic enhancer of the immunoglobulin heavy-chain gene. We have used a cotransfection system to investigate how proteins binding these sites may participate in enhancer-promoter interactions. Basic helix-loop-helix-zipper (BHLHZIP) proteins TFE3 and TFEB activate from a distance in this assay, but the basic zipper (BZIP) protein NF-IL6 and endogenous OCT-binding proteins do not. Our results suggest that remotely bound TFE3 is recruited to the initiation site by association with proximally bound TFE3; this interaction is mediated by the BHLHZIP domain and not by activation domains of TFE3. The BZIP domain of Ig/EBP lacks this activity, revealing an important functional difference between these structurally related dimerization domains. We also show that TFE3 can exist as a tetramer in solution and that tetramerization is determined by the HLHZIP domain. These data support a model in which protein-protein interactions between proximally and remotely bound TFE3 recruit TFE3 to the initiation site for activation. The IgH gene is the first example of a cellular gene in which proximal and distal binding sites are found for a protein capable of mediating enhancer-promoter interaction.     

Short communication: Protoplast formation from the thermophilic fungus Malbranchea sulfurea,using the thermostable chitinase and laminarinase of Paecilomyces varioti

Two thermostable enzymes produced by the thermophilic fungus Paecilomyces varioti, a chitinase and laminarinase, were used to isolate protoplasts of a thermophilic fungus, Malbranchea sulfurea. The frequency of protoplast regeneration observed (35%) was considerably higher than that obtained using commercial lytic enzymes.     

Gametic embryogenesis and callogenesis in Isolated microspore culture of Jatropha curcas L. a recalcitrant bioenergy crop

Plant Cell, Tissue and Organ Culture (PCTOC) - Jatropha curcas is an undomesticated crop and its plantations did not meet commercial expectation due to absence of high yielding commercial line with...     

Synthetic Antimicrobial Peptide Polybia MP-1 (Mastoparan) Inhibits Growth of Antibiotic Resistant Pseudomonas aeruginosa Isolates From Mastitic Cow Milk

International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) offer a potent and effective alternative for treatment of antibiotic resistant microbes. Mastoparans or...     

KINETIC STUDIES OF L-ASPARAGINASE FROM Penicillium digitatum

L-Asparaginase is an enzyme used in the treatment of acute lymphoblastic leukemia and other related malignancies. Its further use includes reduction of asparagine concentration in food products, which may lead to formation of acrylamide. Currently bacterial asparaginase is produced at industrial scale, but the enzyme isolated from bacterial origin is often associated with adverse reactions. These side effects require development of asparaginase from alternative sources. In the present study, Penicillium digitatum was explored for the production of extracellular L-asparaginase using modified Czapek–Dox media. The enzyme was purified about 60.95-fold and then kinetic study showed that the Km value of the enzyme was 1 × 10^?5 M. The optimum pH and temperature for the enzyme were 7.0 and 30°C, respectively. The optimum incubation period for L-asparaginase was 15 min. This work concludes that this enzyme can be a suitable candidate due to its strong kinetic properties, and further research can usher into development of asparaginase formulation from fungal origin with less adverse effects.     

Differential Modulation of TREM2 Protein during Postnatal Brain Development in Mice

During postnatal development, microglia, the resident innate immune cells of the central nervous system are constantly monitoring the brain parenchyma, cleaning the cell debris, the synaptic contacts overproduced and also maintaining the brain homeostasis. In this context, the postnatal microglia need some control over the innate immune response. One such molecule recently described to be involved in modulation of immune response is TREM2 (triggering receptor expressed on myeloid cells 2). Although some studies have observed TREM2 mRNA in postnatal brain, the regional pattern of the TREM2 protein has not been described. We therefore characterized the distribution of TREM2 protein in mice brain from Postnatal day (P) 1 to 14 by immunostaining. In our study, TREM2 protein was expressed only in microglia/macrophages and is developmentally downregulated in a region-dependent manner. Its expression persisted in white matter, mainly in caudal corpus callosum, and the neurogenic subventricular zone for a longer time than in grey matter. Additionally, the phenotypes of the TREM2+ microglia also differ; expressing CD16/32, MHCII and CD86 (antigen presentation markers) and CD68 (phagocytic marker) in different regions as well as with different intensity till P7. The mannose receptor (CD206) colocalized with TREM2 only at P1–P3 in the subventricular zone and cingulum, while others persisted at low intensities till P7. Furthermore, the spatiotemporal expression pattern and characterization of TREM2 indicate towards its other plausible roles in phagocytosis, progenitor’s fate determination or microglia phenotype modulation during postnatal development. Hence, the increase of TREM2 observed in pathologies may recapitulate their function during postnatal development, as a better understanding of this period may open new pathway for future therapies.     

Opto-Mechanical Coupling in Interfaces under Static and Propagative Conditions and Its Biological Implications

Fluorescent dyes are vital for studying static and dynamic patterns and pattern formation in cell biology. Emission properties of the dyes incorporated in a biological interface are known to be sensitive to their local environment. We report that the fluorescence intensity of dye molecules embedded in lipid interfaces is indeed a thermodynamic observable of the system. Opto-mechanical coupling of lipid-dye system was measured as a function of the thermodynamic state of the interface. The corresponding state diagrams quantify the thermodynamic coupling between intensity I and lateral pressure π. We further demonstrate that the coupling is conserved upon varying the temperature T. Notably, the observed opto-mechanical coupling is not limited to equilibrium conditions, but also holds for propagating pressure pulses. The non-equilibrium data show, that fluorescence is especially sensitive to dynamic changes in state such as the LE-LC phase transition. We conclude that variations in the thermodynamic state (here π and T, in general pH, membrane potential V, etc also) of lipid membranes are capable of controlling fluorescence intensity. Therefore, interfacial thermodynamic state diagrams of I should be obtained for a proper interpretation of intensity data.     

Somatic Variations in Cervical Cancers in Indian Patients

There are very few reports that describe the mutational landscape of cervical cancer, one of the leading cancers in Indian women. The aim of the present study was to investigate the somatic mutations that occur in cervical cancer. Whole exome sequencing of 10 treatment naïve tumour biopsies with matched blood samples, from a cohort of Indian patients with locally advanced disease, was performed. The data revealed missense mutations across 1282 genes, out of 1831 genes harbouring somatic mutations. These missense mutations (nonsynonymous + stop-gained) when compared with pre-existing mutations in the COSMIC database showed that 272 mutations in 250 genes were already reported although from cancers other than cervical cancer. More than 1000 novel somatic variations were obtained in matched tumour samples. Pathways / genes that are frequently mutated in various other cancers were found to be mutated in cervical cancers. A significant enrichment of somatic mutations in the MAPK pathway was observed, some of which could be potentially targetable. This is the first report of whole exome sequencing of well annotated cervical cancer samples from Indian women and helps identify trends in mutation profiles that are found in an Indian cohort of cervical cancer.