Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New gene necessary for plant growth and development discovered

13.10.2003


By taking a fresh approach to an old problem, University of California, San Diego biologists and colleagues at other institutions have found a new gene essential for plant growth, a discovery that could lead to the design of better herbicides and even novelty plants.


Images of normal plant (above) and plant exposed to chemical that inactivates the newly discovered gene SIR1 (below)
Credit: Yunde Zhao, UCSD




Despite 100 years of research on auxin, a plant hormone essential in regulating plants’ development and responses to their surroundings, including the ability of plants to grow toward light, much remains unknown about how auxin is synthesized and how it works. A new approach known as “chemical genetics,” in which chemicals are used to regulate activities of proteins produced by specific genes, has revealed a previously unknown gene, SIR1, which functions to keep the effects of auxin in check. The UCSD scientists say that one implication of their discovery is the potential development of environmentally safe herbicides from chemicals that impede the action of auxin by over-activating the SIR1 gene.

A paper featured on the cover of the October 10, 2003 issue of Plant Physiology details the chemical genetic approach. The discovery of the SIR1 gene was reported in the August 22nd issue of Science.


“By using chemical genetics we have been able to identify a new gene that regulates the important plant hormone auxin,” explains Yunde Zhao, assistant professor of biology at UCSD, who was largely responsible for the work. “This finding can be applied to manipulating plant growth, including the development of a new generation of herbicides. Chemical genetics shows a great deal of promise for helping us understand aspects of plant biology, like how auxin is synthesized and controlled, where genetic methods used by researchers until now only had limited success.”

Interestingly, the researchers found that if, at different times, they applied and withdrew the chemical that inactivated the SIR1 protein, this led to strangely shaped plants because SIR1 usually dampens the effect of auxin. Auxin plays important roles in the development of roots, stems and leaves, but either too much or too little auxin interferes with development. Zhao thinks this could have implications for the design of novel flowers and other plant structures.

“Some had leaves that developed into striking trumpet-like shapes,” he says.

Chemical genetics has two major advantages over the genetic approaches traditionally used. First, chemical genetics can permit a researcher to study the effects of more subtle gene changes than eliminating a gene. This is important because a gene may play more than one role, at multiple times during development. If the gene has an essential role early in development, then eliminating it will kill the organism, preventing researchers from discovering other roles for that gene later in development. Since chemical genetics is reversible, by simply stopping the application of a chemical that inactivates or activates a protein produced by a gene, it can be used to study what a gene does at different stages in development.

A second advantage of chemical genetics has to do with the fact that the molecules used can often inactivate related proteins with the same function. A problem with the traditional approach of eliminating a particular gene to determine its function is that if there are two or more genes with the same or similar functions, removing one of those genes may have no apparent effect on the health of the organism. This gene redundancy is more common in plants than in animals.

“About 70% of the genes in the model plant we used in our study, Arabidopsis, may have at least two copies,” Zhao points out. “This is a problem with traditional genetic approaches, but with chemical genetics a small molecule will most likely be able to inactivate all members of a closely related family of proteins provided that they operate by a similar mechanism.”

Both gene redundancy and the lethal effect of eliminating genes essential for plant development have plagued biologists studying auxin for many years. Because chemical genetics can be useful in solving these two problems, Zhao thinks that the application of chemical genetics will likely lead to rapid advances in the field.

While the technique of chemical genetics had been used by researchers working on yeast, bacteria and mammalian cells in culture, its application in plant biology is still at an infancy stage. Zhao cites his background as a biochemist as helping him to come with a fresh perspective to the auxin problem.

“When I started working on plants, I didn’t have much knowledge in plant biology,” Zhao says. “So I wasn’t afraid of taking on those projects the plant biologists didn’t think would work.”

The SIR1 work was initiated by Zhao in the laboratory of Joanne Chory, a Howard Hughes Medical Institute investigator at the Salk Institute for Biological Studies, and continued in Zhao’s own lab at UCSD in collaboration with Xinhua Dai, research associate in biology at UCSD; Helen Blackwell, now assistant professor of chemistry at University of Wisconsin, Madison; and Stuart Schreiber, professor of chemistry at Harvard University and an HHMI investigator. The work was supported by the National Institutes of Health and the Howard Hughes Medical Institute. The Plant Physiology paper on chemical genetic approaches to plant biology was written in collaboration with Helen Blackwell, with support from the NIH.

Sherry Seethaler | UCSD
Further information:
http://ucsdnews.ucsd.edu/newsrel/science/auxingenes.htm
http://www.sdtelecom.org/
http://www.plantphysiol.org/

More articles from Life Sciences:

nachricht Solving the efficiency of Gram-negative bacteria
22.03.2019 | Harvard University

nachricht Bacteria bide their time when antibiotics attack
22.03.2019 | Rice University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>