Salinity Stress Alerts Genome Stability and Genotoxicity of Ocimum basilicum Cultivars

Salinity is an important abiotic stress that greatly influences growth, secondary product content and genotoxicity in plants. Ocimum basilicum L. (family Lamiaceae) produces a volatile oil, which is used in many pharmaceutical industries, but the oil biosynthesis is affected by salt stress. The aim of this study was to evaluate the effect of salinity stress on genome stability and genotoxicity of three basil cultivars (Gigante, Gralissimum and Verde) using comet assays to study the genotoxic impact of salinity stress (0, 50, 100 and 200 mM NaCl) and a semi-quantitative real time polymerase chain reaction to study terpene gene expression. Both analyses revealed considerable genetic effects of salinity stress on the O. basilicum genome, detected by a regular increase in DNA damage and by diversity in the transcript levels of terpene biosynthesis and inhibitor genes. Our findings confirmed that basil plants were affected by NaCl salinity stress and that exposure to 200 mM NaCl resulted in significant DNA damage in the form of tail moment, DNA tail percentage and tail length. The accumulation of linalool synthase enzyme (LS) and hexokinase synthase (HK) gene transcripts was greatly increased in response to salinity, whereas FPPS, GPPS and DXR gene transcription was suppressed in all three basil cultivars. © 2021 Friends Science Publishers

Effect of Bacillus bacteria on activity of pathogen-induced proteins in potato plants and increasing their resistance to Phytophthora infestans (Mont.) de Bary

We studied the effect of the Bacillus bacteria on the content and activity of defensive compounds in potato plants upon infection with late blight pathogen. Bacterial treatment had a stimulating effect on the concentration of H2O2 and transcriptional activity of hydrolase inhibitor genes.

Small Molecule CDK Inhibitors for the Therapeutic Management of Cancer

: Cyclin-dependent kinases (CDKs) are a group of multifunctional enzymes consisting of catalytic and regulatory subunits. The regulatory subunit, cyclin, remains dissociated under normal circumstances, and complexation of cyclin with the catalytic subunit of CDK leads to its activation for phosphorylation of protein substrates. The primary role of CDKs is in the regulation of the cell cycle. Retinoblastoma protein (Rb) is one of the widely investigated tumor suppressor protein substrates of CDK, which prevents cells from entering into cell-cycle under normal conditions. Phosphorylation of Rb by CDKs causes its inactivation and ultimately allows cells to enter a new cell cycle. Many cancers are associated with hyperactivation of CDKs as a result of mutation of the CDK genes or CDK inhibitor genes. Therefore, CDK modulators are of great interest to explore as novel therapeutic agents against cancer and led to the discovery of several CDK inhibitors to clinics. This review focuses on the current progress and development of anti-cancer CDK inhibitors from preclinical to clinical and synthetic to natural small molecules.

Influence of the genus Bacillus bacteria on the content of H2O2 and the activity of hydrolases and their inhibitors in potato plants during Phytophthora infestans Mont. de Bary infection

The authors studied the effect of treatment with bacteria Bacillus subtilis Cohn (strains 26D) and B. thuringiensis Berliner (strain B-6066) on the hydrogen peroxide (H2O2) content, the activity of hydrolytic enzymes and their protein inhibitors in potato plants (Solanum tuberosum L.) in connection with development of resistance to the late blight pathogen - oomycete Phytophthora infestans Mont. de Bary. Studies were carried out on potato plants of the susceptible Early Rose potato cultivar that were treated with a suspension of B. subtilis and B. thuringiensis bacteria (108 cells/ml) and infected with P. infestans (107 spores/ml). A decrease in the degree of leaf damage by oomycete was revealed under the influence of the genus Bacillus bacteria, depending on the strain. The increase in potato resistance to P. infestans infection was mediated by the stimulating effect of the B. subtilis 26D and the B. thuringiensis B-6066 bacteria on the concentration of H2O2, the modulating effect on the activity of hydrolytic enzymes and the enhancement of the transcriptional activity of protease and amylase inhibitor genes in plant tissues. Differences in the degree of activation of the transcriptional activity of hydrolase inhibitor genes by the B. subtilis 26D and the B. thuringiensis B-6066 bacteria were revealed, which suggests differential ways of forming the potato resistance to P. infestans under their influence.

MXD/MIZ1 complexes activate transcription of MYC-repressed genes

ABSTRACTMXD proteins are transcription repressors that antagonize the E-box dependent activation of genes by MYC. MYC together with MIZ1 acts also as a repressor of a subset of genes, including cell cycle inhibitor genes such as p15 and p21. A role of MXDs in regulation of MYC-repressed genes is not known. Here we report that MXDs are functionally expressed in U2OS cells and activate transcription of p15 and p21, and other MYC-repressed genes. Activation of transcription was dependent on the interaction of MXDs with MIZ1, and on an intact DNA binding domain. MIZ1-binding deficient MXD mutants interacted with MAX and were active as repressors of MYC-activated genes but failed to activate MYC-repressed genes. Mutant MXDs with reduced DNA binding affinity interacted with MAX and MIZ1 but neither repressed nor activated transcription. Overexpression of MXDs attenuated proliferation of U2OS cells predominantly via MIZ1-dependent induction of p21. Our data show that MXDs and MYC have a reciprocally antagonistic potential to regulate transcription of mutual target genes.