A land plant phylogenetic framework for GLABROUS INFLORESCENCE STEMS (GIS), SUPERMAN, JAGGED and allies plus their TOPLESS co-repressor

Members of the plant specific family of C1-1i zinc finger transcription factors (ZF-TFs), such as SUPERMAN, JAGGED, KNUCKLES or GIS, regulate diverse developmental processes including sexual reproduction. C1-1is consist of one zinc-finger and one to two EAR domains, connected by large intrinsically disordered regions (IDR). While the role of C1-i1 ZF-TFs in development processes is well known for some genes in Arabidopsis, rice or tomato a comprehensive and broad phylogenetic background is lacking, yet knowledge of orthology is a requirement for a better understanding of C1-1i-Zf-TFs diverse roles in plants. Here, we provide a fine-grained and land plant wide classification of C1-1i sub-families and their known co-repressors TOPLESS and TOPLESS RELATED. Our work combines the identification of orthologous groups with Maximum-Likelihood phylogeny reconstructions and digital gene expression analyses mining high quality land plant genomes and transcriptomes to generate a comprehensive framework of C1-1i ZF-TF evolution. We show that C1-1i’s are low to moderate copy genes and that orthologous genes only partially have conserved sub-family and life cycle stage dependent expression pattern across land plants while others are highly diverged. Our work provides the phylogenetic framework for C1-1i ZF-TFs, s and strengthen C1-1 ZF-TFs as a potential model for IDR-research in plants.