Epigenetic responses to abiotic stresses during reproductive development in cereals

Abstract

Overview of current understanding of epigenetic alterations after abiotic stresses during reproductive development in cereals. Abiotic stresses, including heat, drought, cold, flooding, and salinity, negatively impact crop productivity. Various stages during reproductive development are especially sensitive to environmental stresses, which may lead to complete sterility and severe yield losses. Plants exhibit diverse responses to ameliorate stress damage. Changes in DNA methylation, histone modification as well as regulation of small RNA and long noncoding RNA pathways have been shown to represent key modulators in plant stress responses. During reproductive development in cereals, various protein complexes controlling histone and DNA methylation have been identified, revealing conserved and novel mechanisms regulating abiotic stress responses in cereals and other plant species. New findings highlight the role of transposable elements during stress periods. Here, we review our current understanding of epigenetic stress responses during male and female gametophyte formation (germline development), fertilization, early seed devolvement, and seed maturation in cereals. An integrative model of epigenetic responses during reproductive development in cereals is proposed, emphasizing the role of DNA methylation and histone modifications during abiotic stresses.

Keywords: Abiotic stress; DNA methylation; Fertilization; Germline; Histone modification; Maize; Rice; Seed development; Small RNAs; Wheat.

Fig. 1

Integrative model of the effects of abiotic stresses on the epigenetic status of cereals during reproductive development. Pre-fertilization, early seed development and maturation events in response to stresses are described. The main epigenetic alterations and corresponding molecular players are indicated. See text for detailed explanations