Disrupting MLV integrase:BET protein interaction biases integration into quiescent chromatin and delays but does not eliminate tumor activation in a MYC/Runx2 mouse model

English version

Autoři: Lorenz Loyola ^aff001; Vasudevan Achuthan ^aff002; Kathryn Gilroy ^aff003; Gillian Borland ^aff004; Anna Kilbey ^aff004; Nancy Mackay ^aff004; Margaret Bell ^aff005; Jodie Hay ^aff004; Sriram Aiyer ^aff001; Dylan Fingerman ^aff001; Rodrigo A. Villanueva ^aff001; Ewan Cameron ^aff005; Christine A. Kozak ^aff006; Alan N. Engelman ^aff002; James Neil ^aff004; Monica J. Roth ^aff001
Působiště autorů: Rutgers-Robert Wood Johnson Medical School, Dept of Pharmacology, Piscataway, New Jersey, United States of America ^aff001; Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America ^aff002; Beatson Institute for Cancer Research, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom ^aff003; MRC Univ. of Glasgow Centre for Virus Research, College of Medicine, Veterinary Medicine and Life Sciences, University of Glasgow, Glasgow, United Kingdom ^aff004; Univ. of Glasgow School of Veterinary Medicine, Department of Veterinary Pathology Bearsden, United Kingdom ^aff005; NIH, NIAID, Bethesda, Maryland, United States of America ^aff006; Harvard Medical School, Department of Medicine, Boston, Massachusetts, United States of America ^aff007
Vyšlo v časopise: Disrupting MLV integrase:BET protein interaction biases integration into quiescent chromatin and delays but does not eliminate tumor activation in a MYC/Runx2 mouse model. PLoS Pathog 15(12): e32767. doi:10.1371/journal.ppat.1008154
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.ppat.1008154

Souhrn

Murine leukemia virus (MLV) integrase (IN) lacking the C-terminal tail peptide (TP) loses its interaction with the host bromodomain and extraterminal (BET) proteins and displays decreased integration at promoter/enhancers and transcriptional start sites/CpG islands. MLV lacking the IN TP via an altered open reading frame was used to infect tumorigenesis mouse model (MYC/Runx2) animals to observe integration patterns and phenotypic effects, but viral passage resulted in the restoration of the IN TP through small deletions. Mice subsequently infected with an MLV IN lacking the TP coding sequence (TP^-) showed an improved median survival by 15 days compared to wild type (WT) MLV infection. Recombination with polytropic endogenous retrovirus (ERV), Pmv20, was identified in seven mice displaying both fast and slow tumorigenesis, highlighting the strong selection within the mouse to maintain the full-length IN protein. Mapping the genomic locations of MLV in tumors from an infected mouse with no observed recombination with ERVs, TP^-16, showed fewer integrations at TSS and CpG islands, compared to integrations observed in WT tumors. However, this mouse succumbed to the tumor in relatively rapid fashion (34 days). Analysis of the top copy number integrants in the TP^-16 tumor revealed their proximity to known MLV common insertion sites genes while maintaining the MLV IN TP^- genotype. Furthermore, integration mapping in K562 cells revealed an insertion preference of MLV IN TP^- within chromatin profile states associated with weakly transcribed heterochromatin with fewer integrations at histone marks associated with BET proteins (H3K4me1/2/3, and H3K27Ac). While MLV IN TP^- showed a decreased overall rate of tumorigenesis compared to WT virus in the MYC/Runx2 model, MLV integration still occurred at regions associated with oncogenic driver genes independently from the influence of BET proteins, either stochastically or through trans-complementation by functional endogenous Gag-Pol protein.

Klíčová slova:

Chromatin – DNA methylation – Mammalian genomics – Protein interactions – Genomic libraries – Polymerase chain reaction – Mouse models – Carcinogenesis

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