Jiří Heráček

Kateřina Trejbalová; Jana Blažková; Magda Matouskova; Dana Kučerová; Lubomíra Pecnová; Zdenka Vernerová; Jiří Heráček; Ivan Hirsch; Jiří Hejnar

Syncytin-1 and -2, human fusogenic glycoproteins encoded by the env genes of the endogenous retroviral loci ERVWE1 and ERVFRDE1, respectively, contribute to the differentiation of multinucleated syncytiotrophoblast in chorionic villi. In non-trophoblastic cells, however, the expression of syncytins has to be suppressed to avoid potential pathogenic effects. We studied the epigenetic suppression of ERVWE1 and ERVFRDE1 5′-long terminal repeats by DNA methylation and chromatin modifications. Immunoprecipitation of the provirus-associated chromatin revealed the H3K9 trimethylation at transcriptionally inactivated syncytins in HeLa cells. qRT-PCR analysis of non-spliced ERVWE1 and ERVFRDE1 mRNAs and respective env mRNAs detected efficient splicing of endogenously expressed RNAs in trophoblastic but not in non-placental cells. Pointing to the pathogenic potential of aberrantly expressed syncytin-1, we have found deregulation of transcription and splicing of the ERVWE1 in biopsies of testicular seminomas. Finally, ectopic expression experiments suggest the importance of proper chromatin context for the ERVWE1 splicing. Our results thus demonstrate that cell-specific retroviral splicing represents an additional epigenetic level controling the expression of endogenous retroviruses.

Daniel Housa; Zdenka Vernerová; Jiří Heráček; Bohumír Procházka; Petr Čechák; Jitka Kuncová; Martin Haluzik

Daniel Housa; Zdeňka Vernerová; Jiří Heráček; P. Cechak; B. Rosova; Jitka Kuncová; Martin Haluzik

Jiří Heráček; Vladimír Sobotka; Miluse Vozdova; Jiří Rubeš; Urban Michael; Robert Grill

Tomáš Novotný; Jiří Heráček; Urban Michael

Martin Lukeš; Jiří Heráček

Urban Michael; Jiří Heráček; Jan Hrbáček ml.; Tomáš Novotný

Jan Hrbáček ml.; Jiří Heráček; Tomáš Novotný; Urban Michael

Daniel Housa; Martin Haluzík CSc; Zdena Vernerová CSc; Housová J; Jiří Heráček

Martin Lukeš; Miroslav Záleský; Roman Zachoval; Jiří Heráček; Jana Sachová; Urban Michael