Mapping and engineering of auxin-induced plasma membrane dissociation in BRX family proteins

• DOI: 10.1093/plcell/koab076
• Publication Date: 2021-03-03T12:18:08Z
• Authors: Samuel W H Koh; Petra Marhava; Surbhi Rana; Alina Graf; Bernard Moret; Alkistis E L Bass...; Melina Zourelidou; Martina Kolb; Ulrich Z Hammes; Claus Schwechheimer; Christian S Hardtke
• Keywords: Selaginellaceae; 0301 basic medicine; Indoleacetic Acids; Arabidopsis Proteins; Cell Membrane; Arabidopsis; Plants, Genetically Modified; Recombinant Proteins; Xenopus laevis; 03 medical and health sciences; Biowissenschaften, Biologie; Protein Domains; Gene Expression Regulation, Plant; ddc:570; Multigene Family; Oocytes; ddc:630; Animals; Female

Abstract Angiosperms have evolved the phloem for long-distance transport of metabolites. The complex process development involves genes that only occur in vascular plant lineages. For example, Arabidopsis thaliana, BREVIS RADIX (BRX) gene is required continuous root protophloem differentiation, together with PROTEIN KINASE ASSOCIATED WITH BRX (PAX). and its BRX-LIKE (BRXL) homologs are composed four highly conserved domains including signature tandem separated by variable spacers. Nevertheless, family proteins functionally diverged. instance, BRXL2 can partially replace protophloem. This divergence reflected physiologically relevant differences protein behavior, such as auxin-induced plasma membrane dissociation BRX, which not observed BRXL2. Here we dissected differential functions using a set amino acid substitutions domain swaps. Our data suggest membrane-associated both necessary sufficient to convey biological outputs function therefore constitute an important regulatory entity. Moreover, PAX target phosphosites linker between two mediate dissociation. Engineering these sites into renders this modified auxin-responsive thereby increases activity context.