Cloning of maize chitinase 1 gene and its expression in genetically transformed rice to confer resistance against rice blast caused by Pyricularia oryzae.

Fungal pathogens are one of the major reasons for biotic stress on rice (Oryza sativa L.), causing severe productivity losses every year. Breeding for host resistance is a mainstay of rice disease management, but conventional development of commercial resistant varieties is often slow. In contrast, the development of disease resistance by targeted genome manipulation has the potential to deliver resistant varieties more rapidly. The present study reports the first cloning of a synthetic maize chitinase 1 gene and its insertion in rice cv. (Basmati 385) via Agrobacterium-mediated transformation to confer resistance to the rice blast pathogen, Pyricularia oryzae. Several factors for transformation were optimized; we found that 4-week-old calli and an infection time of 15 minutes with Agrobacterium before colonization on co-cultivation media were the best-suited conditions. Moreover, 300 µM of acetosyringone in co-cultivation media for two days was exceptional in achieving the highest callus transformation frequency. Transgenic lines were analyzed using molecular and functional techniques. Successful integration of the gene into rice lines was confirmed by polymerase chain reaction with primer sets specific to chitinase and hpt genes. Furthermore, real-time PCR analysis of transformants indicated a strong association between transgene expression and elevated levels of resistance to rice blast. Functional validation of the integrated gene was performed by a detached leaf bioassay, which validated the efficacy of chitinase-mediated resistance in all transgenic Basmati 385 plants with variable levels of enhanced resistance against the P. oryzae. We concluded that overexpression of the maize chitinase 1 gene in Basmati 385 improved resistance against the pathogen. These findings will add new options to resistant germplasm resources for disease resistance breeding. The maize chitinase 1 gene demonstrated potential for genetic improvement of rice varieties against biotic stresses in future transformation programs.

Optimization of Prime Editing in Rice, Peanut, Chickpea, and Cowpea Protoplasts by Restoration of GFP Activity.

Precise editing of the plant genome has long been desired for functional genomic research and crop breeding. Prime editing is a newly developed precise editing technology based on CRISPR-Cas9, which uses an engineered reverse transcriptase (RT), a catalytically impaired Cas9 endonuclease (nCas9), and a prime editing guide RNA (pegRNA). In addition, prime editing has a wider range of editing types than base editing and can produce nearly all types of edits. Although prime editing was first established in human cells, it has recently been applied to plants. As a relatively new technique, optimization will be needed to increase the editing efficiency in different crops. In this study, we successfully edited a mutant GFP in rice, peanut, chickpea, and cowpea protoplasts. In rice, up to 16 times higher editing efficiency was achieved with a dual pegRNA than the single pegRNA containing vectors. Edited-mutant GFP protoplasts have also been obtained in peanut, chickpea, and cowpea after transformation with the dual pegRNA vectors, albeit with much lower editing efficiency than in rice, ranging from 0.2% to 0.5%. These initial results promise to expedite the application of prime editing in legume breeding programs to accelerate crop improvement.

Phytochemistry, antioxidant and antibacterial activities of fruit extracts of Myrsine africana L.

Myrsine africana L. a commonly consumed medicinal plant grows in forest of mountains region located at North East of Pakistan. In current study, the fruit extracts were chemically characterized and their bioactivities were determined. Higher quantity of total phenols, total flavonoids and tannins were obtained from methanolic fruit extracts. The HPLC analysis provided higher level of quercetin followed by rutin and p-coumaric acid. Whereas the GC-MS quantification had given significant level of ten saturated and unsaturated fatty acids and some of them were not reported earlier. In vitro study, lower cytotoxic behavior of fruit extracts but higher antioxidant values as well as higher zone of inhibition versus S. aureus, E. coli, K. pneumonia and B. subtilis and Mycobacterium tuberculosis were observed. The organic compounds found in fruit extracts of M. africana correlated well with its used in ethno medicines.

Biogenic iron oxide nanoparticles enhance callogenesis and regeneration pattern of recalcitrant Cicer arietinum L.

This study is the first report on the biosynthesized iron oxide nanoparticles (IONPs) which mediate in-vitro callus induction and shoot regeneration in economically important recalcitrant chickpea crop (Cicer arietinum L.). Here, we used leaf extract of Cymbopogon jwarancusa for the synthesis of IONPs in order to achieve a better biocompatibility. The bioactive compounds in C. jwarancusa leaf extract served as both reducing and capping agents in the fabrication process of IONPs. Field emission scanning electron microscopy (FE-SEM) revealed rods like surface morphology of IONPs with an average diameter of 50±0.2 nm. Energy-dispersive X-ray spectroscopy (EDS) depicted formation of pure IONPs with 69.84% Fe and 30.16% O2. X-ray diffractometry (XRD) and attenuated total reflectance-fourier transform infrared (ATR-FTIR) validate the crystalline structure, chemical analysis detect the presence of various biomolecular fingerprints in the as synthesized IONPs. UV-visible absorption spectroscopy depicts activity of IONPs under visible light. Thermo-gravimetric analysis (TGA) displayed thermal loss of organic capping around 500°C and confirmed their stabilization. The biosynthesized IONPs revealed promising results in callus induction, shoot regeneration and root induction of chickpea plants. Both chickpea varieties Punjab-Noor 09 and Bittle-98 explants, Embryo axes (EA) and Embryo axes plus adjacent part of cotyledon (EXC) demonstrated dose-dependent response. Among all explants, EXC of Punjab-Noor variety showed the highest callogenesis (96%) and shoot regeneration frequency (88%), while root induction frequency was also increased to 83%. Iron content was quantified in regenerated chickpea varieties through inductively coupled plasma-optical emission spectrometry. The quantity of iron is significantly increased in Punjab-Noor regenerated plants (4.88 mg/g) as compare to control treated plants (2.42 mg/g). We found that IONPs enhance chickpea growth pattern and keep regenerated plantlets infection free by providing an optimum environment for rapid growth and development. Thus, IONPs synthesized through green process can be utilized in tissue culture studies in other important recalcitrant legumes crops.

Green fabricated zinc oxide nanoformulated media enhanced callus induction and regeneration dynamics of Panicum virgatum L.

The current study focuses on the usage of bio synthesized zinc oxide nanoparticles to increase the tissue culture efficiency of important forage grass Panicum virgatum. Zinc being a micronutrient enhanced the callogenesis and regeneration efficiency of Panicum virgatum at different concentrations. Here, we synthesized zinc oxide nanoparticles through Cymbopogon citratus leaves extract to evaluate the effect of zinc oxide nanoparticles on plant regeneration ability in switchgrass. X-ray diffraction (XRD) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) validate phase purity of green synthesize Zinc oxide nanoparticles whereas, electron microscopy (SEM) has illustrated the average size of particle 50±4 nm with hexagonal rod like shape. Energy dispersive spectroscopy X-ray (EDS) depicted major peaks of Zn (92.68%) while minor peaks refer to Oxygen (7.32%). ZnO-NPs demonstrated the incredibly promising results against callogenesis. Biosynthesized ZnO-NPs at optimum concentration showed very promising effect on plant regeneration ability. Both the explants, seeds and nodes showed dose dependent response and upon high doses exceeding 40 mg/L the results were recorded negative, whereas at 30 mg/L both explants demonstrated 70% and 76% regeneration frequency. The results conclude that ZnO-NPs enhance the plant growth and development and tailored the nutritive properties at nano-scale. Furthermore, eco-friendly approach of ZnO-NPs synthesis is strongly believed to improve in vitro regeneration frequencies in several other monocot plants.

Chemical profiling and bioactivities on the leaf extracts of Vitex neugundo.

The Vitex negeundo is a widely used medicinal plant which has not been fully investigated in the past. We assessed the in vivo hepatoprotective and in vitro antioxidant, antibacterial, cytotoxicity and anti proliferative study of leaf extracts of V. neugundo. The chemically profiled using HPLC, three flavonoids were quantified and GC-MS analysis revealed the presence of two new compounds those were not reported earlier from the leaf extract of V. neugundo. The animal study was conducted on mice treated with CCl4 using methanolic and chloroform extracts (100, 200 and 300mg/kg b.w), with silymarin as a positive control. Hepatoprotective effects were determined by analyzing blood for liver marker enzymes, direct bilirubins and hematological parameters (RBC, WBC and platelets). The methanolic extract (300mg/kg b.w) has shown the stronger hepatoprotective effects against abnormalities produced by CCl4. The in vivo hepatoprotective effects correlated well with the in vitro antioxidant, cytotoxicity and antiproliferative activities and with high levels of flavonoids and other organic compounds analyzed from plant extracts. The leaf extracts of this plant could be good candidates for lead compound required for the development of antioxidant/anticancer drugs.

Chemical profiling, in vitro and in vivo bioactivities of leaf extracts of Vitex neugundo.

The Vitex negeundo is a widely used medicinal plant which has not been fully investigated in the past. We assessed the in vivo hepatoprotective and in vitro antioxidant, antibacterial, cytotoxicity and antiproliferative study of leaf extracts of V. Neugundo. The chemically profiled using HPLC, three flavonoids were quantified and GC-MS analysis revealed the presence of two new compounds those were not reported earlier. The animal study was conducted on mice treated with CCl4 using methanolic and chloroform extracts (100, 200 and 300 mg/kg b.w), with silymarin as a positive control. Hepatoprotective effects were determined by analyzing blood for liver marker enzymes, direct bilirubins and hematological parameters (RBC, WBC and platelets). The methanolic extract (300 mg/kg b.w) has shown the stronger hepatoprotective effects against abnormalities produced by CCl4. The in vivo hepatoprotective effects correlated well with the in vitro antioxidant, cytotoxicity and antiproliferative activities and with high levels of flavonoids and other organic compounds analyzed from plant extracts. The leaf extracts of this plant could be good candidates for lead compound required for the development of antioxidant/anticancer drugs.

CDKN2A/P16INK4A variants association with breast cancer and their in-silico analysis.

CDKN2A was first identified as melanoma predisposition tumour suppressor gene and has been successively studied. The previous researches have not established any noteworthy association with breast cancer. Therefore, through extensive literature search and in-silico analysis, we have tried to focus on the role of CDKN2A in breast cancer. CDKN2A variants in breast cancer were collected from different databases. The overall percentage of variants (approximately 5.8%) and their incidence frequency in breast cancer cases were found to be very low as compared to the number of samples screened in different studies. Exon 2 was identified as the major region of alternations. Approximately 42.8% were entire gene deletions, while 24.2% were missense mutations. These variants cannot be ignored because of their pathogenic effects as interpreted by the bioinformatics tools used in the present study. Earlier studies have shown that CDKN2A excludes the predisposition of germline variants, but interestingly shares common breast cancer germline variants with other carcinomas. Most of the data have revealed this gene as rarely mutated or deleted in breast cancer. However, few association studies have shown that in addition to being a 'multiple' tumour suppressor gene, it is mutated/deleted more in breast cancer cell lines as compared to breast cancer tissues or blood samples; thus, this gene cannot be neglected as a breast cancer candidate gene. The deletion/malfunctioning of CDKN2A in different tumours including breast cancer has recently led to the discovery of many clinical CDK inhibitors. Furthermore, these collected genetic variants will also be helpful in developing diagnostic, preventive, and treatment approaches for patients.