Featured Research

from universities, journals, and other organizations

Blossoms Of Maturity: Newly Discovered Signaling Pathway Ensures That Plants Remember To Flower

Date:
August 25, 2009
Source:
Max-Planck-Gesellschaft
Summary:
Plants normally flower in response to seasonal changes, such as those associated with the end of winter or beginning of spring. Scientists have now identified a signaling pathway that allows plants to blossom even without positive signals from the environment. The concentration of a small RNA snippet in plants cells operates like an hour glass: a decline in its level awakes the plant from its vegetative dormancy and allows it to enter the reproductive mode.

Electron micrograph of the common wallcress, Arabidopsis thaliana.
Credit: Image by Jόrgen Berger

Why do some plants blossom even when days are short and gray?

Scientists at the Max Planck Institute for Developmental Biology have found the answer to this question: An endogenous mechanism allows them to flower in the absence of external influences such as long days. A small piece of RNA, a so-called microRNA, has a central role in this process, as a decline of its concentration in the shoot apex triggers flowering.

MicroRNAs are very short RNA snippets that have emerged in recent years as essential regulators of gene function in both plants and animals. By binding to complementary motifs in a messenger RNA, they inhibit its translation into protein. This process thus blunts the activity of the corresponding gene.

In Tόbingen, developmental biologists have discovered that the common wallcress, Arabidopsis, uses this regulatory mechanism to switch from vegetative to reproductive development. A group of related regulators, the SPL proteins, play an important role in promoting the onset of flowering. In young plants, production of SPL proteins is prevented by high levels of microRNA156.

Jia-Wei Wang and colleagues demonstrate that independent of external cues, the concentration of the microRNA declines over time, like sand running through an hourglass. When the microRNA concentration falls below a certain level, enough SPL proteins are produced to activate the flowering process even in the absence of other regulators that measure day length or external temperature. This in turns allows a sufficiently old plant to flower, even in an unfavorable environment.

Interestingly, the SPLs do double duty, since they have supporting roles when plants flower in response to long days. Furthermore, both the SPLs and other regulators eventually converge on a similar set of targets crucial for flowering.

"Flowering is crucial for the long-term survival of plants. The redundancy of environment-dependent and –independent mechanisms ensures that plants do not wait forever until flowering. Better flower once, then never," explains Detlef Weigel, director at the Max Planck Institute for Developmental Biology.


Story Source:

The above story is based on materials provided by Max-Planck-Gesellschaft. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jia-Wei Wang, Benjamin Czech, Detlef Weigel. miR156-regulated SPL transcription factors define an endogenous flowering pathway in Arabidopsis thaliana. Cell, August 21, 2009 DOI: 10.1016/j.cell.2009.06.014

Cite This Page:

Max-Planck-Gesellschaft. "Blossoms Of Maturity: Newly Discovered Signaling Pathway Ensures That Plants Remember To Flower." ScienceDaily. ScienceDaily, 25 August 2009. <www.sciencedaily.com/releases/2009/08/090820123931.htm>.
Max-Planck-Gesellschaft. (2009, August 25). Blossoms Of Maturity: Newly Discovered Signaling Pathway Ensures That Plants Remember To Flower. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/2009/08/090820123931.htm
Max-Planck-Gesellschaft. "Blossoms Of Maturity: Newly Discovered Signaling Pathway Ensures That Plants Remember To Flower." ScienceDaily. www.sciencedaily.com/releases/2009/08/090820123931.htm (accessed August 1, 2014).

Share This




More Plants & Animals News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pyrenees Orphan Bear Cub Gets Brand New Home

Pyrenees Orphan Bear Cub Gets Brand New Home

AFP (Aug. 1, 2014) — The discovery of a bear cub in the Pyrenees mountains made headlines in April 2014. Despire several attempts to find the animal's mother, the cub remained alone. Now, the Pyrenees Conservation Foundation has constructed an enclosure. Duration: 00:31 Video provided by AFP
Powered by NewsLook.com
Ebola Vaccine Might Be Coming, But Where's It Been?

Ebola Vaccine Might Be Coming, But Where's It Been?

Newsy (Aug. 1, 2014) — Health officials are working to fast-track a vaccine — the West-African Ebola outbreak has killed more than 700. But why didn't we already have one? Video provided by Newsy
Powered by NewsLook.com
Study Links Certain Birth Control Pills To Breast Cancer

Study Links Certain Birth Control Pills To Breast Cancer

Newsy (Aug. 1, 2014) — Previous studies have made the link between birth control and breast cancer, but the latest makes the link to high-estrogen oral contraceptives. Video provided by Newsy
Powered by NewsLook.com
Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) — Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins