Featured Research

from universities, journals, and other organizations

Work with RNA silencing and plant stem cells may lead to controlling fruit, seed and leaves

Date:
May 20, 2011
Source:
Texas A&M AgriLife Communications
Summary:
Research on controlling the stem cells of plants could eventually lead to learning how to make them produce more fruit, seed and leaves, according to researchers.

Arabidopsis mutations and normal plants. Interfering with microRNA being loaded into a ‘decoy’ protein can cause various mutant phenotypes such as stunted growth in Arabidopsis plants.
Credit: Texas AgriLife Extension Service photo by Robert Burns

Research on controlling the stem cells of plants could eventually lead to learning how to make them produce more fruit, seed and leaves, according to Dr. Xiuren Zhang, Texas AgriLife Research scientist and professor with the Texas A&M University department of biochemistry and biophysics.

Results of a nearly three-year project led by an AgriLife Research team headed by Zhang was published in Cell.

"Working with the shoot meristem area, we may (eventually) control fruit and seed yield or plant mass by manipulating the development and maintenance of plant stem cells. We can also engineer plant shapes by doing this," Zhang said.

In plants, the shoot meristem area is composed of undifferentiated cells, which means they can be programmed by the plant to become various structures -- leaf, stem, branches flower, etc. -- much as mammalian stem cells can be programmed to produce different organs, he said.

The team worked with Arabidopsis, a plant also known as rock cress, which is related to cabbage and mustard. Arabidopsis is often used for studying plant biology because it is the first plant to have its entire genome sequenced.

Previous studies had shown that the an Arabidopsis gene known as argonaute 10, or simply AGO10, plays a critical role in regulating meristem cell development. Arabidopsis has 10 AGO genes, and it was known that AGO10 is involved in various biological processes such as meristem development and proper leaf formation, but by exactly what mechanism it performed these roles was not clear, Zhang said.

"However, although the genetic functions of AGO10 have been described, the molecular mechanism by which it regulates SAM (shoot apical meristem) development remained unknown," Zhang wrote in the Cell article. "Here we demonstrate that AGO10 specifically interacts with miR166/165."

The abbreviation miR166/165 refers to microRNA, a type of small RNA molecule that regulates gene expression, Zhang explained. MicroRNAs are deceptively simple in structure, often only about 20 bases in length, whereas regular RNA may be composed of hundreds or thousands of bases.

Though composed of only a few bases, microRNAs often perform a critical function by switching the expression of certain genes off. Turning off gene expression is just as important a regulatory mechanism in plant development as switching genes on, Zhang noted.

This switching-off function of microRNA has been known for more than a decade. Further work had shown that it is microRNAs that actually guide the argonaute to actually do the switching off, sort of how a software application controls a smart phone or computer, according to Zhang.

Work by Zhang's team had demonstrated that if miR166/165 did not load into AGO10, or the AGO10 gene was missing, then the meristem part of the plant would be deformed, but why this was so remained a mystery.

Zhang and his team proposed that AGO10 functions as "a decoy for miR166/165″ to prevent it being loaded into other AGO proteins, particularly AGO1, which "plays a potent but inhibitory role in correct development of the meristem area cells," he said.

"In other words, if miR166/165 is loaded into AGO1, they would shut their target genes off," Zhang said. "But if miR166/165 is loaded into AGO10 protein, they won't switch-off target genes. Thus, AGO10 works in an opposite way compared to AGO1: It protects target genes and secures their expression."

Other members of the team were: Dr. Martin Dickman, director of the Institute for Plant Genomics and Biotechnology; Dr. Sing-Hoi Sze, associate professor of computer science with the Texas A&M University department of biochemistry and biophysics; Dr. Hongliang Zhu, post-doctorate; technicians Ronghui Wang and Xin Zhou; graduate student, Fuqu Hu and undergraduate students Lisa Wen Liou and Ashley Barefoot.

The work was jointly funded by a National Science Foundation grant and by Texas A&M University and AgriLife Research.


Story Source:

The above story is based on materials provided by Texas A&M AgriLife Communications. Note: Materials may be edited for content and length.


Journal Reference:

  1. Hongliang Zhu, Fuqu Hu, Ronghui Wang, Xin Zhou, Sing-Hoi Sze, LisaWen Liou, Ashley Barefoot, Martin Dickman, Xiuren Zhang. Arabidopsis Argonaute10 Specifically Sequesters miR166/165 to Regulate Shoot Apical Meristem Development. Cell, 2011; 145 (2): 242 DOI: 10.1016/j.cell.2011.03.024

Cite This Page:

Texas A&M AgriLife Communications. "Work with RNA silencing and plant stem cells may lead to controlling fruit, seed and leaves." ScienceDaily. ScienceDaily, 20 May 2011. <www.sciencedaily.com/releases/2011/05/110516121533.htm>.
Texas A&M AgriLife Communications. (2011, May 20). Work with RNA silencing and plant stem cells may lead to controlling fruit, seed and leaves. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2011/05/110516121533.htm
Texas A&M AgriLife Communications. "Work with RNA silencing and plant stem cells may lead to controlling fruit, seed and leaves." ScienceDaily. www.sciencedaily.com/releases/2011/05/110516121533.htm (accessed September 18, 2014).

Share This



More Plants & Animals News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

Raw: Elephant Undergoes Surgery in Tbilisi Zoo

AP (Sep. 18, 2014) Grand the elephant has successfully undergone surgery to remove a portion of infected tusk at Tbilisi Zoo in Georgia. British veterinary surgeons used an electric drill to extract the infected piece. (Sept. 18) Video provided by AP
Powered by NewsLook.com
Chimp Violence Study Renews Debate On Why They Kill

Chimp Violence Study Renews Debate On Why They Kill

Newsy (Sep. 17, 2014) The study weighs in on a debate over whether chimps are naturally violent or become that way due to human interference in the environment. Video provided by Newsy
Powered by NewsLook.com
Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
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