[Increased LAMP1 Expression Enhances SARS-CoV-1 and SARS-CoV-2 Production in Vero-Derived Transgenic Cell Lines].

Coronaviridae is a family of single-stranded RNA (ssRNA) viruses that can cause diseases with high mortality rates. SARS-CoV-1 and MERS-CoV appeared in 2002-2003 and 2012, respectively. A novel coronavirus, SARS-CoV-2, emerged in 2019 in Wuhan (China) and has caused more than 5 million deaths in worldwide. The entry of SARS-CoV-1 into the cell is due to the interaction of the viral spike (S) protein and the cell protein, angiotensin-converting enzyme 2 (ACE2). After infection, virus assembly occurs in Golgi apparatus-derived vesicles during exocytosis. One of the possible participants in this process is LAMP1 protein. We established transgenic Vero cell lines with increased expression of human LAMP1 gene and evaluated SARS-CoV-1 and SARS-CoV-2 production. An increase in the production of both viruses in LAMP1-expressing cells when compared with Vero cells was observed, especially in the presence of trypsin during infection. From these results it can be assumed that LAMP1 promotes SARS-CoV-1 and SARS-CoV-2 production due to enhanced exocytosis.

[Chromatin changes caused by CGG repeat expansion in fmr1 gene].

Fragile X syndrome is inheritable neurodegenerative disease with frequency 1/4000-1/6000. It is the main cause of inheritable mental retardation. Progression of the disorder is caused by CGG repeat expansion in 5' UTR of fmr1 (fragile X mental retardation 1) gene. Normal allele contains ≤ 54 repeats. Allele containing 55-200 repeats induce fragile X-associated disorders: fragile X-associated tremor/ataxia syndrome and fragile-X associated primary ovarian insufficiency. Allele containing ≥ 200 repeats induce fragile X syndrome. Absence of FMRP protein is the main reason for the syndrome progression. FMRP is RNA-binding protein responsible for neuronal differentiation. In case of increasing CGG triplets number the expression of fmr1 gene is repressed. Results of CGG expansion are DNA methylation, histone methylation and deacetylation. Repression transcription factors bind such chromatin and lead to disorder progression. In this review we discuss the mechanisms of heterochromatinization induced by CGG repeat expansion in the promoter region of fmr1 gene.

Increased LAMP1 Expression Enhances SARS-CoV-1 and SARS-CoV-2 Production in Vero-Derived Transgenic Cell Lines.

Coronaviridae is a family of single-stranded RNA (ssRNA) viruses that can cause diseases with high mortality rates. SARS-CoV-1 and MERS-CoV appeared in 2002‒2003 and 2012, respectively. A novel coronavirus, SARS-CoV-2, emerged in 2019 in Wuhan (China) and has caused more than 5 million deaths in worldwide. The entry of SARS-CoV-1 into the cell is due to the interaction of the viral spike (S) protein and the cell protein, angiotensin-converting enzyme 2 (ACE2). After infection, virus assembly occurs in Golgi apparatus-derived vesicles during exocytosis. One of the possible participants in this process is LAMP1 protein. We established transgenic Vero cell lines with increased expression of human LAMP1 gene and evaluated SARS-CoV-1 and SARS-CoV-2 production. An increase in the production of both viruses in LAMP1-expressing cells when compared with Vero cells was observed, especially in the presence of trypsin during infection. From these results it can be assumed that LAMP1 promotes SARS-CoV-1 and SARS-CoV-2 production due to enhanced exocytosis.

Derivation of iPS cell line (ICGi032-A) from a patient affected with fragile X syndrome.

Trinucleotide repeat expansion diseases such as fragile X syndrome are of great interest to study since the mechanism of its development is still unknown. IPS cell lines are some of the most convenient models for studying. The ICGi032-A iPS cell line was obtained from the peripheral blood mononuclear cells of the patient affected with fragile X syndrome. ICGi032-A iPS cell line have a normal karyotype, expression of pluripotency markers and can differentiate in vitro into the cells of three germ layers.

Establishment of an induced pluripotent stem cell line (ICGi026-A) from peripheral blood mononuclear cells of a patient with fragile X syndrome.

Expansion over 200 CGG repeats in FMR1 gene causes inherited intellectual disability or autism spectrum disorder named as fragile X syndrome. Despite the known cause fragile X syndrome pathogenesis has not been specified yet. The ICGi026-A iPSCs line was obtained by the reprogramming of the peripheral blood mononuclear cells from a 9-year-old boy with fragile X syndrome. The ICGi026-A iPSCs expressed pluripotency markers, had a normal male karyotype (46, XY) and had the capacity to in vivo differentiate into the cells of three germ layers.