Identification and functionality prediction of pathogenesis‐related protein 1 from legume family

The production and accumulation of pathogenesis‐related (PR) proteins in plants is one of the important responses to biotic and abiotic stress. Large number of identified PR proteins has been categorized into 17 functional families based on their structure, phylogenetics, and biological activities. However, they are not widely studied in legume crops. Using 29 PR1 proteins from Arabidopsis thaliana, as query, here we have predicted 92 candidate PR1 proteins through the PSI‐BLAST and HMMER programs. These candidate proteins were comprehensively analyzed with, multiple sequence alignment, domain architecture studies, signal peptide, and motif extraction followed by phylogenetic analysis. Further, response of two candidate PR1 proteins from chickpea against Fusarium oxysporum f.sp.ciceri attack was validated using qRT‐PCR followed by their 3D structure prediction. To decipher mode of action for PR1s, docking of pathogen extracellular matrix components along with fungal elicitors was performed with two chickpea PR1 proteins. Based on these findings, we propose carbohydrate to be the unique pathogen‐recognition feature for PR1 proteins and β‐glucanase activity via β‐glucan binding or modification.     

Propagation of mulberry variety – S54 by synseeds of axillary bud

Synseeds were produced from aseptic axillary buds of mulberry variety – S₅₄ (Morus indica L.) to investigate their in vitro and ex vitro conversion potential. The synseeds when cultured on Linsmaier and Skoog's basal medium supplemented with 6-benzyl amino purine (8.88 μM) and 2,3,5-tri iodo benzoic acid (2 μM), produced shoots after 21 days exhibiting 48.2±0.60 in vitro conversion response. The synseeds ex␣vitro conversion response was found to be 45.5±0.76 on soilrite mix containing half strength LS nutrients after 21 days of sowing. Further, synseeds stored at 4 °C for 1–4 months resulted in maximum conversion response under both in vitro and ex vitro conditions, followed by development into complete plantlets without any significant loss of conversion potential. Plants regenerated from the synseeds of axillary bud were hardened, acclimatized and established in soil with varying survival frequency.     

Marine mycoflora of south India with special emphasis on lignicolous marine fungi

A study dealing with the marine fungi associated with decaying wood samples in the brackish water mangrove ecosystem and shoreline ecosystem was carried out in south India. A total of 19 marine fungi were isolated from the brackish water mangrove ecosystem. They included 13 Ascomycetes, one Basidiomycete and five Mitosporic fungi. In terms of percent frequency of occurrence, the most frequent species obtained from the brackishwater were the Lignincola longirostris (16.60%) and Savoryella lignicola (12.09%). Nine species were found frequently. Five species were occasionally encountered. Aigialus mangrovei, Aniptodera mangrovei and Halosarpheia marina were the rare species recorded. The average number of isolates per wood sample was 1.53. A total of 27 marine fungi including 15 ascomycetes, one basidiomycete and ten mitosporic fungi were recorded from the shoreline ecosystem. In terms of percent frequency of occurrence, the most frequent species obtained from Kanyakumari were the Arenariomyces trifurcates (13.66%), Corollospora maritima (12.44%), and Cirrenalia pygmea (10.98%). Seven species were found frequently. Fourteen species were occasionally encountered. Three species were found to be rare in occurrence. The average number of isolates per wood sample was 1.21.     

Differential Responsiveness of Obese (fa/fa) and Lean (Fa/Fa) Zucker Rats to Cytokine-Induced Anorexia

Pathophysiological and pharmacological concentrations of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the cerebrospinal fluid (CSF) induce anorexia in normal rats. Obesity in humans and rodents is associated with increased TNF-α messenger RNA and protein levels in various cell types. This suggests that obese individuals may have differential regulation of cytokine production and dissimilar responsiveness to cytokines. In the present study, we investigated the effects of the intracerebroventricular (ICV) microinfusion of TNF-α (50, 100, and 500 ng/rat), IL-1β (1.0, 4.0, and 8.0 ng), and TNF-α (100 ng) plus IL-1β (1.0 ng) on obese (fa/fa) and lean (Fa/Fa) Zucker rats. The results show that: TNF-α and IL-1β, and the concomitant administration of TNF-a and IL-ip decreased the short-term (4 hours), nighttime (12 hours), and total daily food intakes in obese and lean rats; IL-1β was more potent relative to TNF-α; obese rats showed greater responsiveness to IL-1β: 8.0 ng IL-1β, for example, decreased the 12-hour food intake by 52% in obese and 22% in lean rats. On the other hand, obese and lean rats did not exhibit a significantly different responsiveness to the anorexia induced by 50,100, or 500 ng TNF-α at the 4-hour period; and the concomitant ICV administration of TNF-α and IL-1β induced anorexia with additive (4-hour period) or synergistic (12-hour and 24-hour periods) effects in obese rats. The effect of TNF-α plus IL-1β in lean rats was greater than additive for the 12-hour and 24-hour periods. The difference in suppression of total daily food intake by TNF-α plus IL-1β in obese (-43%) versus lean (-23%) rats was significantly different (p<0.01). The results show that obese (fa/fa) and lean (Fa/Fa) Zucker rats have differential responsiveness to the ICV microinfusion of two different classes of cytokines.     

Hemolysin induces Toll-like receptor (TLR)-independent apoptosis and multiple TLR-associated parallel activation of macrophages

Vibrio cholerae hemolysin (HlyA) displays bipartite property while supervising macrophages (MΦ). The pore-forming toxin causes profound apoptosis within 3 h of exposure and in parallel supports activation of the defying MΦ. HlyA-induced apoptosis of MΦ remains steady for 24 h, is Toll-like receptor (TLR)-independent, and is driven by caspase-9 and caspase-7, thus involving the mitochondrial or intrinsic pathway. Cell activation is carried forward by time dependent up-regulation of varying TLRs. The promiscuous TLR association of HlyA prompted investigation, which revealed the β-prism lectin domain of HlyA simulated TLR4 up-regulation by jacalin, a plant lectin homologue besides expressing CD86 and type I cytokines TNF-α and IL-12. However, HlyA cytolytic protein domain up-regulated TLR2, which controlled CD40 for continuity of cell activation. Expression of TOLLIP before TLR2 and TLR6 abrogated TLR4, CD40, and CD86. We show that the transient expression of TOLLIP leading to curbing of activation-associated capabilities is a plausible feedback mechanism of MΦ to deploy TLR2 and prolong activation involving CD40 to encounter the HlyA cytolysin domain.     

Readers of histone methylarginine marks

Arginine methylation is a common posttranslational modification (PTM) that alters roughly 0.5% of all arginine residues in the cells. There are three types of arginine methylation: monomethylarginine (MMA), asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA). These three PTMs are enriched on RNA-binding proteins and on histones, and also impact signal transduction cascades. To date, over thirty arginine methylation sites have been cataloged on the different core histones. These modifications alter protein structure, impact interactions with DNA, and also generate docking sites for effector molecules. The primary “readers” of methylarginine marks are Tudor domain-containing proteins. The complete family of thirty-six Tudor domain-containing proteins has yet to be fully characterized, but at least ten bind methyllysine motifs and eight bind methylarginine motifs. In this review, we will highlight the biological roles of the Tudor domains that interact with arginine methylated motifs, and also address other types of interactions that are regulated by these particular PTMs. This article is part of a Special Issue entitled: Molecular mechanisms of histone modification function.     

Investigation of 6-[18F]-Fluoromaltose as a Novel PET Tracer for Imaging Bacterial Infection

Despite advances in the field of nuclear medicine, the imaging of bacterial infections has remained a challenge. The existing reagents suffer from poor sensitivity and specificity. In this study we investigate the potential of a novel PET (positron emission tomography) tracer that overcomes these limitations.

Methods

6-[¹⁸F]-fluoromaltose was synthesized. Its behavior in vitro was evaluated in bacterial and mammalian cultures. Detailed pharmacokinetic and biodistribution profiles for the tracer were obtained from a murine model.

Results

6-[¹⁸F]-fluoromaltose is taken up by multiple strains of pathogenic bacteria. It is not taken up by mammalian cancer cell lines. 6-[¹⁸F]-fluoromaltose is retained in infected muscles in a murine model of bacterial myositis. It does not accumulate in inflamed tissue.

Conclusion

We have shown that 6-[¹⁸F]-fluoromaltose can be used to image bacterial infection in vivo with high specificity. We believe that this class of agents will have a significant impact on the clinical management of patients.     

Beyond HLA-A*0201: new HLA-transgenic nonobese diabetic mouse models of type 1 diabetes identify the insulin C-peptide as a rich source of CD8+ T cell epitopes

Type 1 diabetes is an autoimmune disease characterized by T cell responses to β cell Ags, including insulin. Investigations employing the NOD mouse model of the disease have revealed an essential role for β cell-specific CD8(+) T cells in the pathogenic process. As CD8(+) T cells specific for β cell Ags are also present in patients, these reactivities have the potential to serve as therapeutic targets or markers for autoimmune activity. NOD mice transgenic for human class I MHC molecules have previously been employed to identify T cell epitopes having important relevance to the human disease. However, most studies have focused exclusively on HLA-A*0201. To broaden the reach of epitope-based monitoring and therapeutic strategies, we have looked beyond this allele and developed NOD mice expressing human β(2)-microglobulin and HLA-A*1101 or HLA-B*0702, which are representative members of the A3 and B7 HLA supertypes, respectively. We have used islet-infiltrating T cells spontaneously arising in these strains to identify β cell peptides recognized in the context of the transgenic HLA molecules. This work has identified the insulin C-peptide as an abundant source of CD8(+) T cell epitopes. Responses to these epitopes should be of considerable utility for immune monitoring, as they cannot reflect an immune reaction to exogenously administered insulin, which lacks the C-peptide. Because the peptides bound by one supertype member were found to bind certain other members also, the epitopes identified in this study have the potential to result in therapeutic and monitoring tools applicable to large numbers of patients and at-risk individuals.     

Application of the micronucleus test to exfoliated epithelial cells from the oral cavity of beedi smokers, a high-risk group for oral cancer

The primary sites for occurrence of oral cancer include the buccal mucosa, tongue, alveolus, palate, lip and the floor of the mouth. In this study, an attempt was made to estimate the cytogenetic damage in different regions of the oral mucosa in people habituated to smoking beedi,which is one of the major forms of tobacco consumption in India and believed to be a major risk factor for oral cancer. By using the micronucleus assay on exfoliated cells from the buccal mucosa, palate and tongue of beedi smokers, we examined an early cellular response to the effect of beedi smoking. A total number of 50 randomly selected male subjects were included in the study. Case and control groups (smokers and non-smokers, respectively) comprised 25 subjects each. The difference in mean micronucleated cell count between cases and controls was significant (P <0.01) for buccal mucosa and palate, but not for tongue. The correlation between age and micronucleus cell count was weak for both cases (r=0.27) and controls (r=0.36).