Project description:Interactions between plants and each neighboring microbial species are fundamental building blocks that collectively determine the structure and function of the plant microbiota, but the molecular basis of such interactions is poorly characterized. Here, we monocolonized Arabidopsis leaves with nine plant-associated bacteria from all major phyla of the plant microbiota and profiled co-transcriptomes of plants and bacteria. These strains elicited quantitatively different plant transcriptional responses including typical pattern-triggered immunity responses. Genes of non-pathogenic bacteria involved in general metabolism and energy production were commonly suppressed in planta in contrast to a virulent pathogen. Various nutrient acquisition pathways that are frequently encoded in the genomes of plant-associated bacteria were induced in planta in a strain-specific manner, shedding light on bacterial adaptation to the plant environment and identifying a potential driving force of niche separation. Integrative analyses of plant and bacterial transcriptomes suggested that the transcriptional reprogramming of plants is largely uncoupled from that of bacteria at an early stage of interactions. This study provides insights into how plants discriminate among bacterial strains and sets the foundation for in-depth mechanistic dissection of plant-microbiota interactions.
Project description:MicroProteins are short, single domain proteins that act by sequestering larger, multidomain proteins into non-functional complexes. MicroProteins have been identified in plants and animals, where they are mostly involved in the regulation of developmental processes. Here we show that two Arabidopsis thaliana microProteins, miP1a and miP1b, physically interact with CONSTANS (CO) a potent regulator of flowering time. The miP1a/b-type microProteins evolved in dicotyledonous plants and have an additional carboxy-terminal PF(V/L)FL motif. This motif enables miP1a/b microProteins to interact with TOPLESS/TOPLESS-RELATED (TPL/TPR) proteins. Interaction of CO with miP1a/b/TPL causes late flowering due to a failure in the induction of FLOWERING LOCUS T (FT) expression under inductive long day conditions. Both miP1a and miP1b are expressed in vascular tissue, where CO and FT are active. Genetically, miP1a/b act upstream of CO thus our findings unravel a novel layer of flowering time regulation via microProtein-inhibition. RNA-Seq transcriptome analysis of four biological samples were analysed with two technical replicates. Columbia wildtype plants Col-0, constans mutant plants co-SAIL, and two transgenic lines overexpressing a microProtein (miP1a and miP1b) were sequenced.
Project description:MicroProteins are short, single domain proteins that act by sequestering larger, multidomain proteins into non-functional complexes. MicroProteins have been identified in plants and animals, where they are mostly involved in the regulation of developmental processes. Here we show that two Arabidopsis thaliana microProteins, miP1a and miP1b, physically interact with CONSTANS (CO) a potent regulator of flowering time. The miP1a/b-type microProteins evolved in dicotyledonous plants and have an additional carboxy-terminal PF(V/L)FL motif. This motif enables miP1a/b microProteins to interact with TOPLESS/TOPLESS-RELATED (TPL/TPR) proteins. Interaction of CO with miP1a/b/TPL causes late flowering due to a failure in the induction of FLOWERING LOCUS T (FT) expression under inductive long day conditions. Both miP1a and miP1b are expressed in vascular tissue, where CO and FT are active. Genetically, miP1a/b act upstream of CO thus our findings unravel a novel layer of flowering time regulation via microProtein-inhibition.