Interrogating the Functions of PRDM9 Domains in Meiosis

• Published in: Genetics (Austin) 2018-06, Vol.209 (2), p.475-487
• Main Authors: Thibault-Sennett, Sarah, Yu, Qi, Smagulova, Fatima, Cloutier, Jeff, Brick, Kevin, Camerini-Otero, R Daniel, Petukhova, Galina V
• Format: Article
• Language: English
• Subjects: Amino acids; Binding sites; Cell culture; Chromatin; Chromosomes; Clonal deletion; Deoxyribonucleic acid; DNA; DNA methylation; Gene expression; Gene regulation; Genetics; Genomes; Homologous recombination; Homology; Investigations; Life Sciences; Males; Meiosis; Methyltransferase; Mice; MicroRNAs; miRNA; Proteins; Recombination hot spots; Ribonucleic acid; RNA; Transcription; Zinc; Zinc finger proteins
• ISSN: 1943-2631; 0016-6731; 1943-2631
• DOI: 10.1534/genetics.118.300565

Homologous recombination is required for proper segregation of homologous chromosomes during meiosis. It predominantly occurs at recombination hotspots that are defined by the DNA binding specificity of the PRDM9 protein. PRDM9 contains three conserved domains typically involved in regulation of transcription, yet, the role of PRDM9 in gene expression control is not clear. Here we analyze the germline transcriptome of male mice in comparison to males and find no apparent differences in the mRNA and miRNA profiles. We further explore the role of PRDM9 in meiosis by analyzing the effect of the KRAB, SSXRD and post-SET zinc finger deletions in a cell culture expression system and the KRAB domain deletion in mice. We found that although the post-SET zinc finger and the KRAB domains are not essential for the methyltransferase activity of PRDM9 in cell culture, the KRAB domain mutant mice show only residual PRDM9 methyltransferase activity and undergo meiotic arrest. In aggregate, our data indicate that domains typically involved in regulation of gene expression do not serve that role in PRDM9, but are likely involved in setting the proper chromatin environment for initiation and completion of homologous recombination.