Login

GPC Members Login
If you have any problems or have forgotten your login please contact [email protected]


Novel signaling pathway for chilling tolerance in rice revealed

The ability of plants to tolerate chilling stress is fundamental in determining the growing season and geographical distribution of plants. Local temperature anomalies caused by global climate change directly threaten crop production.

Improvement of chilling tolerance in rice varieties requires clarifying the regulatory mechanisms of chilling signaling pathways.

The primary signal transduction pathway of chilling tolerance in rice has been established already, but how the diverse components are regulated is not clear.

OsbHLH002 is one of more than 100 members of the bHLH transcription factor family in rice and has the highest homology with Arabidopsis ICE1 protein, which is one of the core members in the cold signaling pathway in Arabidopsis (hence OsbHLH002 is also called OsICE1).

The research team led by Prof. CHONG Kang from the Institute of Botany of the Chinese Academy of Sciences has revealed a new mechanism for chilling tolerance mediated by OsMAPK3-OsbHLH002-OsTPP1 in rice.

The research team had shown in 2009 that overexpression of the wild rice gene OrbHLH2 enhanced tolerance to osmotic stress in Arabidopsis.

This time they discovered that the cold-activated protein kinase OsMAPK3 phosphorylates the transcription factor OsbHLH002/OsICE1 directly to enhance its transactivation activity.

Moreover, OsMAPK3 attenuated the interaction between OsbHLH002 and E3 ubiquitin ligase OsHOS1, which led to reduced ubiquitination and degradation of OsbHLH002.

The increase of the protein content and transactivation activity of OsbHLH002 effectively activates the expression of OsTPP1 (encoding trehalose-6-phosphatase) to promote the hydrolysis of trehalose-6-phosphate, increasing the trehalose content and enhancing the chilling tolerance of rice.

These results established a novel pathway OsMAPK3-OsbHLH002-OsTPP1. This pathway transduces the cold signal from the kinase cascade system to the nucleus and promotes synthesis of an osmotic protectant to regulate the chilling tolerance in rice.

Read the paper: OsMAPK3 Phosphorylates OsbHLH002/OsICE1 and Inhibits Its Ubiquitination to Activate OsTPP1 and Enhances Rice Chilling Tolerance.

Article source: Chinese Academy of Sciences.

Image credit: XU Yunyuan

News

New 'Buck' naked barley: Food, feed, brew

Researchers at Oregon State University (OSU) are giving an ancient grain a new life: this barley is naked, but not in an indecent way.


Clean and green: A moss that removes lead (Pb) from water

Researchers at the RIKEN Center for Sustainable Resource Science (CSRS) in Japan have demonstrated that that moss can be a green alternative for decontaminating polluted water and soil. Published in PLOS One, the study shows that in particular, the moss Funaria hygrometrica tolerates and absorbs an impressive amount of lead (Pb) from water.


New study shows producers where and how to grow cellulosic biofuel crops

According to a recent ruling by the United States Environmental Protection Agency, 288 million gallons of cellulosic biofuel must be blended into the U.S. gasoline supply in 2018. Although this figure is down slightly from last year, the industry is still growing at a modest pace. However, until now, producers have had to rely on incomplete information and unrealistic, small-scale studies in guiding their decisions about which feedstocks to grow, and where. A new multi-institution report provides practical agronomic data for five cellulosic feedstocks, which could improve adoption and increase production across the country.