2020 Fiscal Year Annual Research Report
Towards integrating the AHL transcription factors into a plant growth gene regulatory network
| Project/Area Number |
19F19781
|
|---|
| Research Institution | Institute of Physical and Chemical Research |
|---|
Principal Investigator |
杉本 慶子 国立研究開発法人理化学研究所, 環境資源科学研究センター, チームリーダー (30455349)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
FAVERO DAVID 国立研究開発法人理化学研究所, 環境資源科学研究センター, 外国人特別研究員
|
|---|
| Project Period (FY) |
2019-11-08 – 2022-03-31
|
| Keywords | AHL / SOB3 / PIF / transcription / growth / plants / photomorphogenesis |
|---|
| Outline of Annual Research Achievements |
The AHL transcription factors are known to repress both hypocotyl and petiole growth.
Past genetic studies combined with data from RNA-seq and ChIP-seq experiments have revealed that SOB3/AHL29 and other AHLs repress petiole elongation by inhibiting the ability of PHYTOCHROME INTERACTING FACTORs (PIFs) to activate the transcription of growth-promoting genes.
However, it is still unknown precisely how AHLs reduce PIF-mediated activation of gene expression, as well as if AHLs repress growth by other PIF-independent mechanisms.
Over the past year, analysis of RNA-seq and ChIP-seq data from both rosettes and seedlings has lead us to the conclusion that AHLs likely repress growth not only by directly inhibiting the transcription of PIF-activated genes, but also by activating the transcription of growth repressors.
These results are further supported by data from transient expression experiments.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
I am close to publishing RNA-seq and ChIP-seq data from short day-grown seedlings, which indicate that although binding of SOB3 is relatively consistent throughout the course of the day, it’s effect on gene expression changes depending on time point. Further, by comparing the effects of SOB3-SRDX and SOB3-VP16 transcription factors to that of wild-type SOB3 both in planta and in the transient expression system, I am formulating a hypothesis regarding the primary mechanism driving AHL-mediated repression of growth. Additionally, I am close to finishing preparations for several experiments that will test the hypothesis that AHLs affect PIF activity at the protein level.
|
| Strategy for Future Research Activity |
By carefully evaluating the effects of SOB3-SRDX and SOB3-VP16 fusion proteins on growth and gene expression, I will establish if AHLs repress growth primarily by acting as repressors or activators of gene transcription. Additionally, I will investigate if AHLs affect PIF protein activity in various ways, for example by promoting their degradation or by directly interfering with their binding to target gene promoters.
|
