Bayesian reconstruction of ancestral expression of the LEA gene families reveals propagule‐derived desiccation tolerance in resurrection plants

Abstract

Desiccation tolerance is a complex trait that is broadly but infrequently present throughout the evolutionary tree of life. Desiccation tolerance has played a significant role in land plant evolution, in both the vegetative and reproductive life history stages. In the land plants, the late embryogenesis abundant (LEA) gene families are involved in both abiotic stress tolerance and the development of reproductive propagules. They are also a major component of vegetative desiccation tolerance. Phylogenies were estimated for four families of LEA genes from Arabidopsis, Physcomitrella, and the desiccation tolerant plants Tortula ruralis, Craterostigma plantagineum, and Xerophyta humilis. Microarray expression data from Arabidopsis and a subset of the Physcomitrella LEAs were used to estimate ancestral expression patterns in the LEA families and to evaluate alternative hypotheses for the origins of vegetative desiccation tolerance in the flowering plants. The results contradict the idea that vegetative desiccation tolerance in the resurrection angiosperms Craterostigma and Xerophyta arose through the co-option of genes exclusively related to stress tolerance, and support the propagule-derived origin of vegetative desiccation tolerance in the resurrection plants.

Ecofisiologia da germinação de sementes de Campomanesia pubescens

“…Em sementes recalcitrantes diversos danos são observados com a secagem (FARIA et al, 2004;MASETTO et al, 2008), enquanto que nas ortodoxas diversos mecanismos são ativados para evitá-los (FISHER, 2008;ANGELOVICI et al, 2010).…”

“…Por outro lado, as sementes recalcitrantes possuem elevado teor de água na maturidade, são intolerantes à dessecação e começam a germinar imediatamente após a fase de maturação, sem passar pela fase de secagem e quiescência metabólica. Vários trabalhos vêm sendo realizados para elucidar a eventual necessidade ou sensibilidade das sementes ao processo de dessecação, sendo de grande importância quantificar esse comportamento (MASETTO et al, 2008;FISHER, 2008;ANGELOVICI et al, 2010).…”

Techonolgy of Qualea grandiflora Mart. (Vochysiaceae) seeds

“…On the other hand, intermediate and recalcitrant seeds have high water content at maturity, are intolerant to desiccation and begin its germination immediately after the ripening stage, without passing through the phases of drying and metabolic quiescence. Several studies have been undertaken to elucidate the possible need or sensitivity of the seeds to the desiccation process, being of great importance to quantify this behavior (ANGELOVICI et al, 2010;FISHER, 2008;MASETTO et al, 2008).…”

“…In recalcitrant seeds, a diverse range of damages is observed with drying (FARIA et al, 2004;MASETTO et al, 2008), while in orthodox seeds various mechanisms are activated to prevent such harms (ANGELOVICI et al, 2010;FISHER, 2008). In orthodox seeds, drying acts as a signal for the passage of the state of development to germination (ANGELOVICI et al, 2010;CATUSSE et al, 2008).…”

An Investigation of the Phylogeny and Evolutionary Processes of Deliquescent Fruiting Bodies in the Mushroom Family Psathyrellaceae (Agaricales)

“…TextWrangler (Bare Bones Software Inc.), which Bayestraits needs to be able to read files (Fisher, 2008).…”