H2020Individual fellowship2021–2023

MASTER · Role of DNA methylation reprogramming in germline stress response

Horizon 2020 — Marie Skłodowska-Curie Actions

Duration
2021-04-01 → 2023-03-31
EU contribution
€224,934
Participants
1
Scheme
MSCA-IF

Lines connect the coordinator with its partners.

Results in brief

Role of DNA methylation reprogramming in germline stress response

Although the male germline DNA methylomes and their dynamics have been well studied, how the methylation pattern was established in germ cells was elusive. Our discoveries elucidate essential methylation and regulatory mechanisms in plant germlines that mediate intergenerational heredity, and establish a novel epigenetic paradigm in how germlines perceive and respond to stress. Our discoveries reveal a new mechanism suggesting how DNA methylation was established in male germ cells directed by its nurse cells. Above all, our works indicate how this pathway mentioned above is involved in the ambient temperature sense, uncovering a novel molecular regulation mechanism in plant germline thermotolerance, which is believed to impact the relative research field. The overall objectives have been successfully achieved including 1) Elucidate DNA methylation reprogramming in the Arabidopsis germline, 2) Determine the role of methylation reprogramming in mediating male thermotolerance, 3) Uncover the biological functions of methylation reprogramming in the germline.

Data: CORDIS, © European Union

Project objective

Cytosine methylation is an ancient epigenetic modification that carries essential regulatory functions in eukaryotic genomes. This modification is reprogramed in both male and female germlines of mammals, regulating essential germline functions. My host lab discovered that DNA methylation reprogramming also occurs in male germlines of flowering plants, such as Arabidopsis, rice and maize. This reprogramming is catalyzed by the RNA-directed DNA methylation pathway (RdDM), which methylates hundreds of genes specifically in the male germline. In Arabidopsis, this germline-specific methylation (GSM) regulates male meiosis by controlling gene transcription and splicing. It is unknown if methylation reprogramming also occurs in plant female germlines. Furthermore, our preliminary data suggest that GSM is modulated by ambient temperature. It is mysterious if and how environmental modulation of methylation reprogramming contributes to stress tolerance in plant germlines. I propose to answer these questions in Arabidopsis using a combination of single-cell genomics, epigenetics, genetics and developmental biology approaches. My preliminary work detected GSM in the egg companion cell and gynoecium (female organ), whose development was reported to be affected by RdDM mutations. Data also suggest that heat-induced modulation of GSM activates a heat shock gene in male meiocytes. Thus, I hypothesize that methylation reprogramming occurs and plays essential regulatory roles in the female germline, and beyond; an important function of such reprogramming is to mediate germline response to environmental stresses such as heat. Here, I will test this hypothesis and elucidate the scope, mechanism and environmental adaptation function of germline reprogramming. My discoveries will elucidate essential methylation and regulatory mechanisms in plant germlines that mediate intergenerational heredity, and establish a novel epigenetic paradigm in how germlines perceive and respond to stress.

Original text from CORDIS.

Participants

Links

Data: CORDIS, © European Union