Sensory plastid-localized proteins trigger epigenetic reprogramming as a component of environmental sensing in plants
Open Access
- Author:
- Jeh, Ha Eun
- Graduate Program:
- Plant Biology
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- June 12, 2024
- Committee Members:
- Teh-Hui Kao, Program Head/Chair
Sally Mackenzie, Chair & Dissertation Advisor
Erin Connolly, Outside Unit & Field Member
Hong Ma, Major Field Member
Jesse Lasky, Major Field Member - Keywords:
- epigenetics
sensory plastid
retrograde signaling
plant stress response
transgenerational memory - Abstract:
- Plants respond to various environmental cues to adjust to their environment, and epigenetic response is involved in this process. Sensory plastids are organelles specialized for environmental sensing in epidermal, vascular, meristem, and reproductive tissues. Perturbation of the sensory plastid-localized protein MutS HOMOLOG 1 (MSH1) induces heritable epigenetic reprogramming associated with altered growth and stress response, but whether this process is MSH1-specific or characteristic of sensory plastid proteins is unclear. The perturbation of a putative MSH1 interactor, PsbP DOMAIN-CONTAINING PROTEIN 3 (PPD3), also induced heritable epigenetic changes for bimodal growth and stress response. The ppd3 mutant was altered in meristem development, and MSH1 and PPD3 co-localization was evident in the root tip. Gene expression and DNA methylome data sets from PPD3 overexpression lines and derived ‘memory’ states showed enrichment in growth versus defense networks and meristem effects associated with plant phenotype. Expansion of our study to hub network analysis of gene expression and DNA methylome in two additional sensory plastid protein mutants, cue1 and sal1, also revealed environmental sensing-related gene networks. The networks identified overlapped with datasets from histone deacetylase 6 (hda6), which was epistatic with the sensory plastid mutants. Epistatic interactions as well as gene expression and DNA methylome effects in hda6 and sensory plastid mutants were daylength-dependent, supporting HDA6 as an epigenetic integrator of daylength and environmental signals from sensory plastids. Results from these studies support a model of sensory plastid signals that trigger HDA6-mediated epigenetic reprogramming in response to environmental changes.