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Antagonistic interactions among different functional guilds of nematodes have been recognized for quite some time, but the underlying explanatory mechanisms are unclear. We investigated responses of tomato (Solanum lycopersicum) to two functional guilds of nematodes - plant parasite (Meloidogyne javanica) and entomopathogens (Heterorhabditis bacteriophora, Steinernema feltiae belowground, and S. carpocapsae) - as well as a leaf mining insect (Tuta absoluta) aboveground. Our results indicate that entomopathogenic nematodes (EPNs): 1) reduced root knot nematode (RKN) infestation belowground, 2) reduced herbivore (T. absoluta) host preference and performance aboveground, and 3) induced overlapping plant defense responses by rapidly activating polyphenol oxidase (PPO) and guaiacol peroxidase (GP) activity in roots, but simultaneously suppressing this activity in aboveground tissues. Concurrently, we investigated potential plant signaling mechanisms underlying these interactions using transcriptome analyses. We found that both entomopathogens and plant parasites triggered immune responses in plant roots with shared gene expression. Secondary metabolite transcripts induced in response to the two nematode functional guilds were generally overlapping and showed an analogous profile of regulation. Likewise, we show that EPNs modulate plant defense against RKN invasion, in part, by suppressing active expression of antioxidant enzymes. Inoculations of roots with EPN triggered an immune response in tomato via up-regulated phenylpropanoid metabolism and synthesis of protease inhibitors (PIs) in plant tissues, which may explain decreased egg laying and developmental performance exhibited by herbivores on EPN-inoculated plants. Furthermore, changes induced in the volatile organic compound (VOC)-related transcriptome indicated that M. javanica and/or S. carpocapsae inoculation of plants triggered both direct and indirect defenses. Our results support the hypothesis that plants 'mistake' subterranean EPNs for parasites, and these otherwise beneficial worms activate a battery of plant defenses associated with systemic acquired resistance (SAR) and/or induced systemic resistance (ISR) with concomitant antagonistic effects on temporally co-occurring subterranean plant pathogenic nematodes and terrestrial herbivores.

Imprinted genes display biased expression of paternal and maternal alleles in mammals. They are marked through epigenetic process during gametogenesis. Characterization of imprinted genes has expanded our understanding of the regulation and function of genes. In the current study, 22 experimentally validated imprinted genes in bovine (Bos Taurus) were analysed. Several supervised machine learning algorithms and attribute weighting methods were used to find characteristics of different types of imprinted genes and suggest a classification method for finding maternally and paternally expressed genes in bovine. For assessing the best model and comparing attributes in other organisms, we have also conducted a comparative analysis for human and sheep imprinted genes. According to the results of the present study, GC contents 10 and 100 kb upstream, Gly and Gln amino acids, Ile/ATC codon usage, LINE and SINE in 100kbup and length of first intron were significantly different between the maternal and paternal genes in cattle. Considering all species together, we found that GC content 100 kb up, LINE 100 kb up and the frequency of amino acids like Gly, Gln and Met were the most important attributes for identifying the paternal and maternal imprinted genes. These findings could imply conservation pattern in the attributes among these species.

The use of anticancer peptides (ACPs) as an alternative/complementary strategy to conventional chemotherapy treatments has been shown to decrease drug resistance and/or severe side effects. However, the efficacy of the positively-charged ACP is inhibited by elevated levels of negatively-charged cell-surface components which trap the peptides and prevent their contact with the cell membrane. Consequently, this decreases ACP-mediated membrane pore formation and cell lysis. Negatively-charged heparan sulphate (HS) and chondroitin sulphate (CS) have been shown to inhibit the cytotoxic effect of ACPs. In this study, we propose a strategy to promote the broad utilization of ACPs. In this context, we developed a drug repositioning pipeline to analyse transcriptomics data generated for four different cancer cell lines (A549, HEPG2, HT29, and MCF7) treated with hundreds of drugs in the LINCS L1000 project. Based on previous studies identifying genes modulating levels of the glycosaminoglycans (GAGs) HS and CS at the cell surface, our analysis aimed at identifying drugs inhibiting genes correlated with high HS and CS levels. As a result, we identified six chemicals as likely repositionable drugs with the potential to enhance the performance of ACPs. The codes in R and Python programming languages are publicly available in https://github.com/ElyasMo/ACPs_HS_HSPGs_CS. As a conclusion, these six drugs are highlighted as excellent targets for synergistic studies with ACPs aimed at lowering the costs associated with ACP-treatment. This article is protected by copyright. All rights reserved.