CRISPR-Cas12a (Cpf1): A Versatile Tool in the Plant Genome Editing Tool Box for Agricultural Advancement

Global population is predicted to approach 10 billion by 2050, an increase of over 2 billion from today. To meet the demands of growing, geographically and socio-economically diversified nations, we need to diversity and expand agricultural production. This expansion of agricultural productivity will need to occur under increasing biotic, and environmental constraints driven by climate change. Clustered regularly interspaced short palindromic repeats-site directed nucleases (CRISPR-SDN) and similar genome editing technologies will likely be key enablers to meet future agricultural needs. While the application of CRISPR-Cas9 mediated genome editing has led the way, the use of CRISPR-Cas12a is also increasing significantly for genome engineering of plants. The popularity of the CRISPR-Cas12a, the type V (class-II) system, is gaining momentum because of its versatility and simplified features. These include the use of a small guide RNA devoid of trans-activating crispr RNA, targeting of T-rich regions of the genome where Cas9 is not suitable for use, RNA processing capability facilitating simpler multiplexing, and its ability to generate double strand breaks (DSB) with staggered ends. Many monocot and dicot species have been successfully edited using this Cas12a system and further research is ongoing to improve its efficiency in plants, including improving the temperature stability of the Cas12a enzyme, identifying new variants of Cas12a or synthetically producing Cas12a with flexible PAM sequences. In this review we provide a comparative survey of CRISPR-Cas12a and Cas9, and provide a perspective on applications of CRISPR-Cas12 in agriculture.

CRISPR-based assays for rapid detection of SARS-CoV-2

COVID-19 pandemic posed an unprecedented threat to global public health and economies. There is no effective treatment of the disease, hence, scaling up testing for rapid diagnosis of SARS-CoV-2 infected patients and quarantine them from healthy individuals is one the best strategies to curb the pandemic. Establishing globally accepted easy-to-access diagnostic tests is extremely important to understanding the epidemiology of the present pandemic. While nucleic acid based tests are considered to be more sensitive with respect to serological tests but present gold standard qRT-PCR-based assays possess limitations such as low sample throughput, requirement for sophisticated reagents and instrumentation. To overcome these shortcomings, recent efforts of incorporating LAMP-based isothermal detection, and minimizing the number of reagents required are on rise. CRISPR based novel techniques, when merge with isothermal and allied technologies, promises to provide sensitive and rapid detection of SARS-CoV-2 nucleic acids. Here, we discuss and present compilation of state-of-the-art detection techniques for COVID-19 using CRISPR technology which has tremendous potential to transform diagnostics and epidemiology.

Scrutinizing the influence of UV radiation on adsorption behavior of zinc metal on marine diatom Nitzschia sp. BDU DD 002

The present study is an investigation into the adsorption of zinc metal on marine diatom Nitzschia sp. under the influence of ultraviolet radiation to reveal the possible role of radiation in metal biomineralization. Nitzschia sp. was isolated from marine habitat and gradually acclimatized to UVA, UVB, and zinc (30 mg/L). The culture was subjected to various concentrations of zinc (5, 10, 15, 20 mg/L) with an artificial exposure of PAR, PAR + UVA, and PAR + UVB radiation. The adsorption isotherm models were applied for validating the hypothesis stating the association of zinc adsorption with exposure to ultraviolet radiation. Altered functional groups on the surface were observed in the FTIR spectra along with changes in antioxidant activity, superoxide dismutase activity, pigment and protein contents due to increased zinc concentration and ultraviolet radiation. Scanning electron micrographs (SEM-EDAX) supported the microscopic morphology of adsorbed metals.