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Introduction: Schizophrenia (SZ) is a common psychiatric neurodevelopmental disorder with a complex genetic architecture. Genomic association studies indicate the involvement of transcription factors in the pathogenesis of SZ. A recent GWAS showed a significant association of ZNF536 with SZ. To date, the molecular functions of ZNF536 are poorly understood and its possible role in the pathogenesis of SZ is unclear. Objectives: The aim of this work was to develop a model cell line for study ZNF536-mediated pathogenic mechanisms associated with SZ. Methods: To assess the spatial interaction of ZNF536 with SZ risk loci, we used the Capture-C method. For ZNF536 deletion, SH-SY5Y was sequentially transduced with two lentiviral vectors. The first expressed Cas9 under the control of a tetracycline regulated promoter and the second expressed a pair of sgRNAs for ZNF536 deletion. Puromycin was used to select transduced cells. Stably transduced cells were then treated with oxytetracycline to induce Cas9 expression. In parallel, SH-SY5Y were transduced with lentiviral constructs of Cas9 and sgRNA carrying a spacer lacking targets in the human genome to obtain a negative control. Individual clones were obtained by the limiting dilution method. The ZNF536 deletion was confirmed by PCR and Sanger sequencing. Results: A spatial interaction of ZNF536 with SZ risk loci was found, suggesting its involvement in SZ pathogenesis. Using the CRISPR/Cas9 system, we obtained several clones with heterozygous deletion of ZNF536. We observed that their growth and proliferation were significantly slowed down. In addition, the mutant clones spontaneously differentiate into a neuron-like phenotype in low-serum medium. Conclusions: We established a cellular model to study ZNF536-mediated mechanisms associated with SZ. Disclosure of Interest: None Declared [ABSTRACT FROM AUTHOR]

Herpesviruses are widespread in the human population. Herpes simplex virus type 1 (HSV1) alone infects more than 3.7 billion people. In most of these, the virus establishes a latent form resistant to the action of all antiviral drugs. Moreover, completely drug-resistant strains of herpesviruses are known, which has prompted the search for alternative approaches to the treatment of herpesviruses, including genome editing with prokaryotic CRISPR/Cas. The CRISPR/Cas9 system of Streptococcus pyogenes effectively suppresses HSV1 infection when expressed from genome-integrated lentiviral vectors. However, there are concerns about the safety of this approach. Here we describe the system built upon the plasmid-encoded CRISPR/Cas9 targeted against UL52 and UL29 genes of the HSV1 primase–helicase complex. The construct was transfected into Vero cells with no significant cytotoxic effects detected. Complete suppression of HSV1 infection within two days was observed, raising the possibility that the proposed plasmid-expressed CRISPR/Cas9 system may be used for the screening of genes important for the HSV1 life cycle and for development of novel strategies for targeted therapy of herpesvirus infections. [ABSTRACT FROM AUTHOR]

Abstract—: The concept of essential genes, whose loss of functionality results in cell death, is one of the fundamental concepts of genetics and is important for basic and applied research. This field is particularly promising in oncology, because using the search for genetic vulnerabilities of cancer cells it is possible to identify new potential targets for antitumor therapy. The modern biotechnology capacities are used in large-scale projects for sequencing of somatic mutations in tumors, as well as for direct action on the genetic apparatus of cancer cells. They provided accumulation of a considerable body of knowledge about genetic variants and their phenotypic manifestations in tumors. In the near future this knowledge will find application in clinical practice. This review describes the main experimental and computational approaches to the search for essential genes with special emphasis on application of these methods in molecular oncology. [ABSTRACT FROM AUTHOR]

Let G be a connected graph on n ≥ 2 vertices with girth at least g such that the length of a maximal chain of successively adjacent vertices of degree 2 in G does not exceed k ≥ 1. Denote by u(G) the maximum number of leaves in a spanning tree of G. We prove that u(G) ≥ αg,k(υ(G) − k − 2) + 2 where αg,1=g+124g+12+1 and αg,k=12k+2 for k ≥ 2. We present an infinite series of examples showing that all these bounds are tight. [ABSTRACT FROM AUTHOR]

A vertex coloring of a graph is called dynamic if the neighborhood of any vertex of degree at least 2 contains at least two vertices of distinct colors. Similarly to the chromatic number χ(G) of a graph G, one can define its dynamic number χd(G) (the minimum number of colors in a dynamic coloring) and dynamic chromatic number χ2(G) (the minimum number of colors in a proper dynamic coloring). We prove that χ2(G) ≤ χ(G) · χd(G) and construct an infinite series of graphs for which this bound on χ2(G) is tight.For a graph G, set k=2ΔGδG We prove that χ2(G) ≤ (k+1)c. Moreover, in the case where k ≥ 3 and Δ(G) ≥ 3, we prove the stronger bound χ2(G) ≤ kc. [ABSTRACT FROM AUTHOR]