Survey and phylogenetic analysis of culturable microbes in the oral secretions of three bark beetle species

In a recent study, we reported a previously undescribed behavior in which a bark beetle exuded oral secretions containing bacteria that have antifungal properties, and hence defend their galleries against pervasive antagonistic Hyphomycete fungi. Actinobacteria, a group known for their antibiotic properties, were the most effective against fungi that invade the spruce beetle galleries. In the present study, we describe the isolation and identification of microorganisms from oral secretions of three bark beetles (Coleoptera: Curculionidae: Scolytinae): the spruce beetle, Dendroctonus rufipennis Kirby, the mountain pine beetle, Dendroctonus ponderosae Hopkins, and the pine engraver, Ips pini Say. Bacteria isolated from these three species span the major bacterial classes α-, β-, and γ-Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, except for D. ponderosae , which yielded no α-proteobacteria or Bacteroidetes isolates. Spruce beetles and pine engraver beetles had similar numbers of α-proteobacteria isolates, but pine engravers yielded twice as many Bacteroidetes isolates as spruce beetles. In contrast, mountain pine beetles yielded more isolates in the β- and γ-proteobacteria than spruce beetles and pine engravers. The highest percentage of Actinobacteria was obtained from spruce beetles, followed by pine engravers and mountain pine beetles. All of the fungal isolates obtained from the three beetle species were Ascomycetes. The greatest fungal diversity was obtained in spruce beetles, which had nine species, followed by pine engravers with five, and mountain pine beetles with one.     

Structural elucidation, modification and characterization of seed gum from Cassia javahikai seeds: A non-traditional source of industrial gums

A water-soluble seed gum was isolated from seed endosperm of Cassia javahikai. The acid-catalyzed fragmentation, methylation, selective enzymatic degradation and periodate oxidation suggested a heteropolymeric structure for the polysaccharide. The polysaccharide was shown to have a linear chain of β(1 → 4) linked d-mannopyranosyls units with side chains of α(1 → 6) d-galactopyranosyl units. Grafting of polyacrylamide onto the gum was performed using K₂S₂O₈/ascorbic acid redox system in presence of Ag⁺ as catalyst at 35 ± 2 °C. The viscosity of the gum solution increased on grafting and the grafted gum was observed to resist biodegradation for more than 256 h. Thermogravimetric analysis revealed that grafted gum was more thermally stable than native gum.     

Translocation of cell-penetrating peptides and delivery of their cargoes in triticale microspores

Microspore culture is contributing significantly in the field of plant breeding for crop improvement in general and cereals, in particular. In the present study, we investigated the uptake of fluorescently labeled cell-penetrating peptides (CPP; Tat, Tat₂, M-Tat, peptide vascular endothelial-cadherin, transportan) in the freshly isolated triticale microspores (mid-late uninucleate stage). We demonstrated that Tat (RKKRRQRRR) and Tat₂ (RKKRRQRRRRKKRRQRRR) are able to efficiently transduce GUS enzyme (272 kDa) in its functional form in 5 and 14% of the microspores, respectively, in a noncovalent manner. Pep-1, a synthetic CPP, was able to transduce GUS enzyme in its active form in 31% of the microspores. The effect of various endocytic and macropinocytic inhibitors on Tat₂-mediated GUS enzyme delivery was studied and revealed a preferred micropinocytosis entry. DNase I protection assay and confocal laser microscopy was carried out to recommend a ratio of 4:1 Tat₂-linear plasmid DNA (pActGUS) in complex preparation for microspore transfection. We further show that Tat₂ can successfully deliver GUS gene in near to 2% triticale microspores. The negative control mutated Tat (M-Tat: AKKRRQRRR) failed to transducer the GUS protein and transfect the GUS gene in microspore nucleus. The ability of CPPs to deliver macromolecules (protein as well as linear plasmid DNA) noncovalently has been demonstrated in triticale isolated microspores. It further confirms potential applications of CPPs in developing simple, time saving, cost effective plant genetic engineering technologies.     

Changes in Phenolics, Polyphenol Oxidase and its Isoenzyme Patterns in Relation to Resistance in Taro against Phytophthora colocasiae

The effect of Phytophthora leaf blight disease, caused by Phytophthora colocasiae Raciborski, on the accumulation of phenolics and polyphenol oxidase (PPO) activity in ex vitro plants was studied in three resistant (DP‐25, Duradim and Jhankri) and one susceptible (N‐118) genotypes of taro [Colocasia esculenta (L). Schott]. The inoculation of taro leaves with P. colocasiae spores resulted in a quantitative change in both biochemical parameters and induction of PPO isoforms in resistant genotypes. The amount of phenolics was increased owing to blight by 68.02%, 58.87%, 52.67% and 11.50% in DP‐25, Duradim, Jhankri and N‐118, respectively. The per cent increase in PPO under stress over non‐stress condition was also highest in DP‐25 (49.14%) followed by Duradim (41.56%), Jhankri (40.55%) and N‐118 (17.08%). The resistant genotypes showed higher activity of PPO as compared with susceptible ones, which was reflected through its banding pattern in isoenzyme analysis, detecting four different isoforms. The intensity of the bands was higher in the resistant genotypes than in susceptible N‐118. The appearance of high intensity bands and/or reduction in the intensity of particular isoform(s) in the zymograms of all the three resistant taro genotypes studied, led to the apparent conclusion of linking PPO isoenzyme expression with blight resistance in taro. The blight incidence (per cent leaf infection and leaf area infection) was lower in the resistant genotypes than in susceptible, N‐118. The yield reduction owing to blight was below 20% in DP‐25, Jhankri and Duradim, while the same was more than 40% in N‐118. The phenolics and PPO activity was negatively correlated with disease incidence and yield reduction owing to blight. Based on the results of disease incidence, biochemical contents and yield, the pattern of stress tolerance was DP‐25 > Duradim > Jhankri > N‐118. The studied parameters, i.e. phenolics and PPO could be used as biochemical markers for leaf blight stress tolerance studies in taro.     

Modeling of the potential coiled-coil structure of snapin protein and its interaction with SNARE complex

Autism is a developmental disability causing learning and memory disorder. The heart of the search for a cure for this syndrome is the need to understand dendrite branch patterning, a process crucial for proper synaptic transmission. Due to the association of snapin with the SNARE complex and its role in synaptic transmission it is reported as a potential drug target for autism therapies. We wish to impart the noesis of the 3D structure of the snapin protein, and in this chase we predict the native structure from its sequence of amino acid residues using the classical Comparative protein structure modeling methods. The predicted protein model can be of great assistance in understanding the structural insights, which is necessary to understand the protein function. Understanding the interactions between snapin and SNARE complex is crucial in studying its role in the neurotransmitter release process. We also presented a computational model that shows the interaction between the snapin and SNAP-25 protein, a part of the larger SNARE complex.     

LncRNA VEAL2 regulates PRKCB2 to modulate endothelial permeability in diabetic retinopathy

Long non‐coding RNAs (lncRNAs) are emerging as key regulators of endothelial cell function. Here, we investigated the role of a novel vascular endothelial‐associated lncRNA (VEAL2) in regulating endothelial permeability. Precise editing of veal2 loci in zebrafish (veal2 ^gib005Δ8/+) induced cranial hemorrhage. In vitro and in vivo studies revealed that veal2 competes with diacylglycerol for interaction with protein kinase C beta‐b (Prkcbb) and regulates its kinase activity. Using PRKCB2 as bait, we identified functional ortholog of veal2 in humans from HUVECs and named it as VEAL2. Overexpression and knockdown of VEAL2 affected tubulogenesis and permeability in HUVECs. VEAL2 was differentially expressed in choroid tissue in eye and blood from patients with diabetic retinopathy, a disease where PRKCB2 is known to be hyperactivated. Further, VEAL2 could rescue the effects of PRKCB2‐mediated turnover of endothelial junctional proteins thus reducing hyperpermeability in hyperglycemic HUVEC model of diabetic retinopathy. Based on evidence from zebrafish and hyperglycemic HUVEC models and diabetic retinopathy patients, we report a hitherto unknown VEAL2 lncRNA‐mediated regulation of PRKCB2, for modulating junctional dynamics and maintenance of endothelial permeability.     

First evidence of putrescine involvement in mitigating the floral malformation in mangoes: A scanning electron microscope study

Floral malformation is the most destructive disease in mangoes. To date, the etiology of this disease has not been resolved. There are indications that stress-stimulated ethylene production might be responsible for the disease. Putrescine mediates various physiological processes for normal functioning and cellular metabolism. Here, the effect of putrescine in concentration ranging from 10^?1 to 10^?3 M was evaluated on disease incidence during mango flowering seasons of 2012 and 2013. In a scanning electron microscopy (SEM) study, putrescine (10^?2 M)-treated malformed floral buds bloomed into opened flowers with separated sepals and/or petals like healthy, whereas the untreated (control) malformed buds remained deformed. Further, malformed flowers recovered upon putrescine treatment, displaying clearly bilobed anthers, enclosing a large number of normal pollen grains and functional ovary with broad stigmatic surface as compared to control. The present findings provide the first report to demonstrate the role of putrescine in reducing various adverse effects of stress ethylene via decelerating the higher pace of its biosynthesis. It stabilizes the normal morphology, development, and functions of malformed reproductive organs to facilitate successful pollination, fertilization, and, thereby, fruit set in mango flowers. However, putrescine–ethylene-mediated cell signaling network, involving various genes to trigger the response, which regulates a wide range of developmental and physiological processes leading to normal cell physiology, needs to be investigated further.