Autosomal recessive variants c.953A>C and c.97-1G>C in NSUN2 causing intellectual disability: a molecular dynamics simulation study of loss-of-function mechanisms.

Introduction: Intellectual disability (ID) is a clinically and genetically heterogeneous disorder. It drastically affects the learning capabilities of patients and eventually reduces their IQ level below 70. Methods: The current genetic study ascertained two consanguineous Pakistani families suffering from autosomal recessive intellectual developmental disorder-5 (MRT5). We have used exome sequencing followed by Sanger sequencing to identify the disease-causing variants. Results and discussion: Genetic analysis using whole exome sequencing in these families identified two novel mutations in the NSUN2 (NM_017755.5). Family-A segregated a novel missense variant c.953A>C; p.Tyr318Ser in exon-9 of the NSUN2. The variant substituted an amino acid Tyr318, highly conserved among different animal species and located in the functional domain of NSUN2 known as "SAM-dependent methyltransferase RsmB/NOP2-type". Whereas in family B, we identified a novel splice site variant c.97-1G>C that affects the splice acceptor site of NSUN2. The identified splice variant (c.97-1G>C) was predicted to result in the skipping of exon-2, which would lead to a frameshift followed by a premature stop codon (p. His86Profs*16). Furthermore, it could result in the termination of translation and synthesis of dysfunctional protein, most likely leading to nonsense-mediated decay. The dynamic consequences of NSUN2 missense variant was further explored together with wildtype through molecular dynamic simulations, which uncovered the disruption of NSUN2 function due to a gain in structural flexibility. The present molecular genetic study further extends the mutational spectrum of NSUN2 to be involved in ID and its genetic heterogeneity in the Pakistani population.

Phytochemical and Biological Screening of Leaf, Bark and Fruit Extracts from Ilex dipyrena Wall.

The Aquifoliaceae is an important family and has been used traditionally for some time. One of the members of this family is the Ilex dipyrena wall, which itself possesses a potential medicinal importance. This plant is traditionally used for the treatment of various ailments including pain, swelling, burns, and fever. The current study was designed to screen out the antioxidant and analgesic potential of this plant and to verify its traditional uses, along with its phytochemical profile. Extracts were subjected to antioxidant, analgesic, and phytochemical analysis using DPPH, chemical-induced (acetic acid and formalin) nociception models and GC-MS analysis, respectively. The leaf, bark, and fruit extracts showed significant antioxidant activity compared to that of standard. Likewise, all the extracts demonstrated significant (p < 0.01) analgesic activity in a mice model. In acetic acid induced analgesia, the leaf, bark, and fruit extracts caused 51.64, 56.13 and 59.52% inhibition, respectively at a dose of 100 mg/kg while at 200 mg/kg it showed 83.01, 71.69 and 75.47% inhibition, respectively. In Formalin-induced paw-licking assay, fruit extract showed 59.42 and 64.19% inhibition at 200 mg/kg dose in the first and second phase, respectively. The GC-MS analysis revealed the presence of cathinone, phenylpropanolamine, dl-phenylephrine, amphetamine, myristic acid, and palmitic acid. Results of the study suggest that crude extracts from different parts of this plant may be a useful source for the development of novel analgesics. However, further investigation in terms of isolation of bioactive compounds and their toxicological evaluations are needed to validate the observed results.

Pharmacognostic and phytochemical studies of Zanthoxylum armatum DC.

The pharmacognostic and phytochemical investigations on the leaf, stem bark, and fruit of Zanthoxylum armatum were carried out. Macroscopic study of leaf, stem bark, and fruit of Z. armatum revealed some of the characteristic features like size, shape, color, odor and taste of the crude drug. Distinguishing fragments were identified from the powder drug. Leaf, bark, and fruit powder of this plant have higher values of total, acid insoluble, and water soluble ash as compared to the powder of this plant exhausted with ethanol and n- hexane. Extraction values in methanol were highest for leaves (20.10%) and fruit (11%), while bark showed highest value in chloroform (8.5%). The extractive values varied among other parts with different solvents. Fluorescence analysis of the Z. Armatum leaf, stem bark, and fruit powder with various reagents showed characteristic coloration at day and under UV light. Quantitative phytochemical screening revealed the presence of many bioactive constituents in leaves, such as alkaloids (15.60±0.10 mg/g), sterols (71.60±0.10mg/g), saponins (21.57±0.12mg/g), tannins (34.43±0.21mg/g), phenols (11.66±0.33mg/g) and flavonoids (13.68±0.66mg/g). Alkaloids (19.60±0.10mg/g), sterols (33.83±0.29mg/g), saponins (14.78±0.10mg/g), tannins (28.62±0.13mg/g), phenols (16.48±1.33mg/g) and flavonoids (18.33±1.22mg/g) were reported form the bark, while fruits were reported to have alkaloids (25.07±0.21mg/g), sterols (164.92±0.14mg/g), saponins (28.60±0.10mg/g), tannins (35.5±0.5mg/g), phenols (21.68±0.44mg/g) and flavonoids (22.8±1.33mg/g). Z. armatum is an important medicinal plant, traditionally used for various ailments. This study will be helpful in the future pharmacognostic standardization of this important plant.

Gibberellins Producing Endophytic Fungus Porostereum spadiceum AGH786 Rescues Growth of Salt Affected Soybean.

In the pursuit of sustainable agriculture through environment and human health friendly practices, we evaluated the potential of a novel gibberellins (GAs) producing basidiomycetous endophytic fungus Porostereum spadiceum AGH786, for alleviating salt stress and promoting health benefits of soybean. Soybean seedlings exposed to different levels of NaCl stress (70 and 140 mM) under greenhouse conditions, were inoculated with the AGH786 strain. Levels of phytohormones including GAs, JA and ABA, and isoflavones were compared in control and the inoculated seedlings to understand the mechanism through which the stress is alleviated. Gibberellins producing endophytic fungi have been vital for promoting plant growth under normal and stress conditions. We report P. spadiceum AGH786 as the ever first GAs producing basidiomycetous fungus capable of producing six types of GAs. In comparison to the so for most efficient GAs producing Gibberella fujikuroi, AGH786 produced significantly higher amount of the bioactive GA3. Salt-stressed phenotype of soybean seedlings was characterized by low content of GAs and high amount of ABA and JA with reduced shoot length, biomass, leaf area, chlorophyll contents, and rate of photosynthesis. Mitigation of salt stress by AGH786 was always accompanied by high GAs, and low ABA and JA, suggesting that this endophytic fungus reduces the effect of salinity by modulating endogenous phytohormones of the seedlings. Additionally, this strain also enhanced the endogenous level of two isoflavones including daidzen and genistein in soybean seedlings under normal as well as salt stress conditions as compared to their respective controls. P. spadiceum AGH786 boosted the NaCl stress tolerance and growth in soybean, by modulating seedlings endogenous phytohormones and isoflavones suggesting a valuable contribution of this potent fungal biofertilizer in sustainable agriculture in salt affected soils.