TY - JOUR A1 - Cuong Nguyen Huu, A1 - Kappel, Christian A1 - Keller, Barbara A1 - Sicard, Adrien A1 - Takebayashi, Yumiko A1 - Breuninger, Holger A1 - Nowak, Michael D. A1 - Bäurle, Isabel A1 - Himmelbach, Axel A1 - Burkart, Michael A1 - Ebbing-Lohaus, Thomas A1 - Sakakibara, Hitoshi A1 - Altschmied, Lothar A1 - Conti, Elena A1 - Lenhard, Michael T1 - Presence versus absence of CYP734A50 underlies the style-length dimorphism in primroses JF - eLife N2 - Heterostyly is a wide-spread floral adaptation to promote outbreeding, yet its genetic basis and evolutionary origin remain poorly understood. In Primula (primroses), heterostyly is controlled by the S-locus supergene that determines the reciprocal arrangement of reproductive organs and incompatibility between the two morphs. However, the identities of the component genes remain unknown. Here, we identify the Primula CYP734A50 gene, encoding a putative brassinosteroid-degrading enzyme, as the G locus that determines the style-length dimorphism. CYP734A50 is only present on the short-styled S-morph haplotype, it is specifically expressed in S-morph styles, and its loss or inactivation leads to long styles. The gene arose by a duplication specific to the Primulaceae lineage and shows an accelerated rate of molecular evolution. Thus, our results provide a mechanistic explanation for the Primula style-length dimorphism and begin to shed light on the evolution of the S-locus as a prime model for a complex plant supergene. Y1 - 2016 U6 - https://doi.org/10.7554/eLife.17956 SN - 2050-084X VL - 5 PB - eLife Sciences Publications CY - Cambridge ER - TY - JOUR A1 - Stief, Anna A1 - Altmann, Simone A1 - Hoffmann, Karen A1 - Pant, Bikram Datt A1 - Scheible, Wolf-Rüdiger A1 - Bäurle, Isabel T1 - Arabidopsis miR156 regulates tolerance to recurring environmental stress through SPL transcription factors JF - The plant cell N2 - Plants are sessile organisms that gauge stressful conditions to ensure survival and reproductive success. While plants in nature often encounter chronic or recurring stressful conditions, the strategies to cope with those are poorly understood. Here, we demonstrate the involvement of ARGONAUTE1 and the microRNA pathway in the adaptation to recurring heat stress (HS memory) at the physiological and molecular level. We show that miR156 isoforms are highly induced after HS and are functionally important for HS memory. miR156 promotes sustained expression of HS-responsive genes and is critical only after HS, demonstrating that the effects of modulating miR156 on HS memory do not reflect preexisting developmental alterations. miR156 targets SPL transcription factor genes that are master regulators of developmental transitions. SPL genes are posttranscriptionally downregulated by miR156 after HS, and this is critical for HS memory. Altogether, the miR156-SPL module mediates the response to recurring HS in Arabidopsis thaliana and thus may serve to integrate stress responses with development. Y1 - 2014 U6 - https://doi.org/10.1105/tpc.114.123851 SN - 1040-4651 SN - 1532-298X VL - 26 IS - 4 SP - 1792 EP - 1807 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Kabelitz, Tina A1 - Kappel, Christian A1 - Henneberger, Kirstin A1 - Benke, Eileen A1 - Noeh, Christiane A1 - Bäurle, Isabel T1 - eQTL mapping of transposon silencing reveals a position-dependent stable escape from epigenetic silencing and transposition of AtMu1 in thee arabidopsis lineage JF - The plant cell N2 - Transposons are massively abundant in all eukaryotic genomes and are suppressed by epigenetic silencing. Transposon activity contributes to the evolution of species; however, it is unclear how much transposition-induced variation exists at a smaller scale and how transposons are targeted for silencing. Here, we exploited differential silencing of the AtMu1c transposon in the Arabidopsis thaliana accessions Columbia (Col) and Landsberg erecta (Ler). The difference persisted in hybrids and recombinant inbred lines and was mapped to a single expression quantitative trait locus within a 20-kb interval. In Ler only, this interval contained a previously unidentified copy of AtMu1c, which was inserted at the 39 end of a protein-coding gene and showed features of expressed genes. By contrast, AtMu1c(Col) was intergenic and associated with heterochromatic features. Furthermore, we identified widespread natural AtMu1c transposition from the analysis of over 200 accessions, which was not evident from alignments to the reference genome. AtMu1c expression was highest for insertions within 39 untranslated regions, suggesting that this location provides protection from silencing. Taken together, our results provide a species-wide view of the activity of one transposable element at unprecedented resolution, showing that AtMu1c transposed in the Arabidopsis lineage and that transposons can escape epigenetic silencing by inserting into specific genomic locations, such as the 3' end of genes. Y1 - 2014 U6 - https://doi.org/10.1105/tpc.114.128512 SN - 1040-4651 SN - 1532-298X VL - 26 IS - 8 SP - 3261 EP - 3271 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Sicard, Adrien A1 - Stacey, Nicola A1 - Hermann, Katrin A1 - Dessoly, Jimmy A1 - Neuffer, Barbara A1 - Bäurle, Isabel A1 - Lenhard, Michael T1 - Genetics, evolution, and adaptive significance of the selfing syndrome in the genus Capsella JF - The plant cell N2 - The change from outbreeding to selfing is one of the most frequent evolutionary transitions in flowering plants. It is often accompanied by characteristic morphological and functional changes to the flowers (the selfing syndrome), including reduced flower size and opening. Little is known about the developmental and genetic basis of the selfing syndrome, as well as its adaptive significance. Here, we address these issues using the two closely related species Capsella grandiflora (the ancestral outbreeder) and red shepherd's purse (Capsella rubella, the derived selfer). In C. rubella, petal size has been decreased by shortening the period of proliferative growth. Using interspecific recombinant inbred lines, we show that differences in petal size and flower opening between the two species each have a complex genetic basis involving allelic differences at multiple loci. An intraspecific cross within C. rubella suggests that flower size and opening have been decreased in the C. rubella lineage before its extensive geographical spread. Lastly, by generating plants that likely resemble the earliest ancestors of the C. rubella lineage, we provide evidence that evolution of the selfing syndrome was at least partly driven by selection for efficient self-pollination. Thus, our studies pave the way for a molecular dissection of selfing-syndrome evolution. Y1 - 2011 U6 - https://doi.org/10.1105/tpc.111.088237 SN - 1040-4651 VL - 23 IS - 9 SP - 3156 EP - 3171 PB - American Society of Plant Physiologists CY - Rockville ER -