AUTHOR=Mapar Mona , Chopra Divykriti , Stephan Lisa , Schrader Andrea , Sun Hequan , Schneeberger Korbinian , Albani Maria , Coupland George , Hülskamp Martin 

TITLE=Genetic and Molecular Analysis of Root Hair Development in Arabis alpina

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.767772

DOI=10.3389/fpls.2021.767772

ISSN=1664-462X

ABSTRACT=<p>Root hair formation in <italic>Arabidopsis thaliana</italic> is a well-established model system for epidermal patterning and morphogenesis in plants. Over the last decades, many underlying regulatory genes and well-established networks have been identified by thorough genetic and molecular analysis. In this study, we used a forward genetic approach to identify genes involved in root hair development in <italic>Arabis alpina</italic>, a related crucifer species that diverged from <italic>A. thaliana</italic> approximately 26–40 million years ago. We found all root hair mutant classes known in <italic>A. thaliana</italic> and identified orthologous regulatory genes by whole-genome or candidate gene sequencing. Our findings indicate that the gene-phenotype relationships regulating root hair development are largely conserved between <italic>A. thaliana</italic> and <italic>A. alpina</italic>. Concordantly, a detailed analysis of one mutant with multiple hairs originating from one cell suggested that a mutation in the <italic>SUPERCENTIPEDE1</italic> (<italic>SCN1</italic>) gene is causal for the phenotype and that <italic>AaSCN1</italic> is fully functional in <italic>A. thaliana</italic>. Interestingly, we also found differences in the regulation of root hair differentiation and morphogenesis between the species, and a subset of root hair mutants could not be explained by mutations in orthologs of known genes from <italic>A. thaliana</italic>. This analysis provides insight into the conservation and divergence of root hair regulation in the Brassicaceae.</p>