How plants learned to respond to changing environments

July 12, 2007

A team of John Innes centre scientists lead by Professor Nick Harberd have discovered how plants evolved the ability to adapt to changes in climate and environment. Plants adapt their growth, including key steps in their life cycle such as germination and flowering, to take advantage of environmental conditions.

They can also repress growth when their environment is not favourable. This involves many complex signalling pathways which are integrated by the plant growth hormone gibberellin.

Publishing in the journal Current Biology, the researchers looked at how plants evolved this ability by looking at the genes involved in the gibberellin signalling pathway in a wide range of plants. They discovered that it was not until the flowering plants evolved 300 million years ago that plants gained the ability to repress growth in response to environmental cues.

All land plants evolved from an aquatic ancestor, and it was after colonisation of the land that the gibberellin mechanism evolved. The earliest land plants to evolve were the bryophyte group, which includes liverworts, hornworts and ancestral mosses, many of which still exist today. The ancestral mosses have their own copies of the genes, but the proteins they make do not interact with each other and can’t repress growth. However, the moss proteins work the same as their more recently evolved counterparts when transferred into modern flowering plants.

The lycophyte group, which evolved 400 million years ago, were the first plants to evolve vascular tissues - specialized tissues for transporting water and nutrients through the plant. This group of plants also have the genes involved in the gibberellin signalling mechanism, and the products of their genes are able to interact with each other, and the hormone gibberellin. However this still does not result in growth repression. Not until the evolution of the gymnosperms (flowering plants) 300 million years ago are these interacting proteins able to repress growth. This group of plants became the most dominant, and make up the majority of plant species we see today.

Evolution of this growth control mechanism appears to have happened in a series of steps, which this study is able to associate with major stages in the evolution of today’s flowering plants. It also involves two types of evolutionary change. As well as structural changes that allow the proteins to interact, flowering plants have also changed the range of genes that are turned on and off in response to these proteins. This work was supported by the Biotechnology and Biological Sciences Research Council.

Source: Norwich BioScience Institutes

Explore further: Manduca sexta caterpillars' developed surprising detoxification mechanism against their host plant's sweet toxin

Related Stories

Can trees really change sex?

November 5, 2015

The revelation that the UK's oldest tree is showing signs of switching sex has sparked much excitement in the world of horticultural science. The Fortingall yew (main image) in Perthshire, Scotland, having apparently spent ...

Marginal soil can make for good biofuel crops

October 23, 2015

Switchgrass, a perennial native to the tallgrass prairie, is one of the most promising bioenergy crops in the United States, with potential to provide high-yield biomass on marginal soils unsuitable for traditional agricultural ...

Root microbiome engineering improves plant growth

September 25, 2015

Humans have been breeding crops until they're bigger and more nutritious since the early days of agriculture, but genetic manipulation isn't the only way to give plants a boost. In a review paper published on September 25 ...

Recommended for you

NASA's space-station resupply missions to relaunch

November 29, 2015

NASA's commercial space program returns to flight this week as one of its private cargo haulers, Orbital ATK, is to launch its first supply shipment to the International Space Station in more than 13 months.

CERN collides heavy nuclei at new record high energy

November 25, 2015

The world's most powerful accelerator, the 27 km long Large Hadron Collider (LHC) operating at CERN in Geneva established collisions between lead nuclei, this morning, at the highest energies ever. The LHC has been colliding ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.