ABSTRACT: Developmental flower transcriptomes of two recently evolved cleistogamous species and their sister chasmogamous species in the mycoheterotrophic genus Gastrodia
Project description:Developmental flower transcriptomes of the chasmogamous species Gastrodia nipponica that is a sister species of cleistogamous Gastrodia takeshimesis
Project description:Developmental flower transcriptomes of the chasmogamous species Gastrodia fontinalis that is a sister species of cleistogamous Gastrodia kuroshimensis
Project description:The annual cleistogamous herb Cardamine kokaiensis is an endemic plant along the Kokai River in Japan. We examined the differences in gene expression patterns among cleistogamous (CL), intermediate (INT), and chasmogamous (CH) flower by cross-species microarray analysis using an Arabidopsis thaliana Affymetrix high-density oligonucleotide microarray (GeneChip ATH1). We then discuss the molecular basis of the evolution of cleistogamy. Our results help to clarify the molecular basis of the evolution of plant mating systems that depend on environmental conditions. Keywords: flower type comparison
Project description:We used flower bud transcriptomes from Collinsia rattanii and its predominantly outcrossing sister species, C. linearis, to explore the genomic basis of mating system and phenotypic evolution in Collinsia, a self-compatible genus. Transcriptional regulation of enzymes involved in pollen formation may influence floral traits that distinguish selfing and outcrossing Collinsia species through pleiotropic functions. These patterns provide clues about parallel evolution in selfing plants.
Project description:The annual cleistogamous herb Cardamine kokaiensis is an endemic plant along the Kokai River in Japan. We examined the differences in gene expression patterns among cleistogamous (CL), intermediate (INT), and chasmogamous (CH) flower by cross-species microarray analysis using an Arabidopsis thaliana Affymetrix high-density oligonucleotide microarray (GeneChip ATH1). We then discuss the molecular basis of the evolution of cleistogamy. Our results help to clarify the molecular basis of the evolution of plant mating systems that depend on environmental conditions. CITATION: Ecogenomics of cleistogamous and chasmogamous flowering: genome-wide gene expression patterns from cross-species microarray analysis in Cardamine kokaiensis (Brassicaceae); Journal of Ecology 2008; Shin-Ichi Morinaga, Atsushi J. Nagano, Saori Miyazaki, Minoru Kubo, Taku Demura, Hiroo Fukuda, Satoki Sakai, Mitsuyasu Hasebe Experiment Overall Design: gDNA hybridyzation data was used to calibration of cross-species microarray using Affymetrix ATH1. CH, INT, and CL flowers of C. kokaiensis were induced the chilling treatment before germination for 14 days or after germination for 14 or 28 days, respectively. We performed two biological replications per flower. Data analysis was conducted according to Hammond et al. (2005) that described the methods of calibration by gDNA hybridization.
Project description:Whether, and to what extent, phenotypic evolution follows predictable genetic paths, remains an important question in evolutionary biology. Convergent evolution of similar characters provides a unique opportunity to address this question. The transition to selfing and the associated changes in flower morphology are among the most prominent examples of repeated evolution in plants. Yet, to date no studies have directly compared the extent of similarities between convergent adaptations to selfing. In this study, we take advantage of the independent transitions to self-fertilization in the genus Capsella to test the existence of genetic and developmental constraints imposed on flower evolution in the context of the selfing syndrome. While C. rubella and C. orientalis have emerged independently, both have evolved almost identical flower characters. Not only the evolutionary outcome is identical but, in both cases, the same developmental strategies underlie the convergent reduction of flower size. This has been associated with convergent evolution of gene-expression changes. The transcriptomic changes common to both selfing lineages are enriched in genes with low-network connectivity and with organ-specific expression patterns. Comparative genetic mapping also indicates that, at least in the case of petal size evolution, these similarities are largely caused by mutations at the same loci. Together, these results suggest that the limited availability of low-pleiotropy paths predetermine closely related species to similar evolutionary outcomes.
Project description:RNA-seq reads from the outcrossing species Arabidopsis lyrata were produced from flowers to study the consequences of the transition from the ancestral state (outcrossing) to the derived state (selfing) that is observed in the sister species Arabidopsis thaliana. This was done in the context of examining another species pair (Capsella rubella versus Capsella grandiflora, which are selfing and outcrossing, respectively). These samples were generated to complement part of this larger study. Briefly, the shift from outcrossing to selfing is common in flowering plants, but neither the genomic consequences nor the speed with which they appear are well understood. An excellent model for understanding the evolution of self fertilization is provided by Capsella rubella, which became self-compatible <200,000 years ago. We present a reference genome for the species, and compare RNA expression and polymorphism patterns between C. rubella and its outcrossing progenitor C. grandiflora. There is a clear shift in the expression of genes associated with flowering phenotypes; a similar shift is seen in the related genus Arabidopsis, where self-fertilization evolved about 1 million years ago. DNA sequence polymorphisms distinguishing the two Capsella species reveal rapid genome-wide relaxation of purifying selection in C. rubella but without a concomitant change in transposable element abundance. Overall, we document that the transition to selfing may be typified by shifts in expression for genes that function in pollen and flower development, along with a measurable reduction of purifying selection. As part of a cross-species comparison of gene expression, RNA-seq data was generated in biological replication (2 replicates) from Arabidopsis lyrata at the floral stage. In total, two samples (biological replicates) were used. The reference strain was used for the experments (strain MN47). Resulting data about gene expression was used as part of a larger study. The Capsella rubella and Capsella grandiflora data are included in GEO Series GSE45518.
Project description:RNA-seq reads from the outcrossing species Arabidopsis lyrata were produced from flowers to study the consequences of the transition from the ancestral state (outcrossing) to the derived state (selfing) that is observed in the sister species Arabidopsis thaliana. This was done in the context of examining another species pair (Capsella rubella versus Capsella grandiflora, which are selfing and outcrossing, respectively). These samples were generated to complement part of this larger study. Briefly, the shift from outcrossing to selfing is common in flowering plants, but neither the genomic consequences nor the speed with which they appear are well understood. An excellent model for understanding the evolution of self fertilization is provided by Capsella rubella, which became self-compatible <200,000 years ago. We present a reference genome for the species, and compare RNA expression and polymorphism patterns between C. rubella and its outcrossing progenitor C. grandiflora. There is a clear shift in the expression of genes associated with flowering phenotypes; a similar shift is seen in the related genus Arabidopsis, where self-fertilization evolved about 1 million years ago. DNA sequence polymorphisms distinguishing the two Capsella species reveal rapid genome-wide relaxation of purifying selection in C. rubella but without a concomitant change in transposable element abundance. Overall, we document that the transition to selfing may be typified by shifts in expression for genes that function in pollen and flower development, along with a measurable reduction of purifying selection.