AtCHE1, the Arabidopsis homolog of mammalian AATF/Che-1 protein, is involved in safeguarding genome stability

Both endogenous and exogenous genotoxins can inflict damage on cellular DNA, leading to reduced genomic stability in plants, which adversely affects development. Apoptosis Antagonizing Transcription Factor (AATF), also referred to as Che-1, has been identified as a binding protein for RNA polymerase II. It plays a crucial role in various cellular processes, including cell proliferation, transcriptional regulation, apoptosis, DNA damage response, and ribosome biogenesis in mammals. In this study, we identify the che1 mutant derived from an ethyl methanesulfonate (EMS)-mutagenized Arabidopsis Col-0 population, characterized by a short root and small leaf phenotype. The underlying mutation is a G-to-A transition located at the boundary of the eighth intron and ninth exon of the AT5G61330 gene, resulting in a misprocessed mRNA transcript. AtCHE1, a homolog of the mammalian AATF/Che-1, contains both the conserved AATF/Che-1 and TRAUB domains in Arabidopsis. Under standard conditions, the che1 mutant exhibits an accumulation of damaged DNA, cell death, and differentiation defects at the root tip. Collectively, these findings underscore the importance of AtChe-1 in meristem maintenance and genome stability.