Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. 24/7 Space News .




EARLY EARTH
Gardener's delight offers glimpse into the evolution of flowering plants
by Staff Writers
Seattle WA (SPX) Sep 06, 2012


Wild-type Thalictrum used in the study have blossoms with stamens, carpels and other organs for sexual reproduction and seed making. Credit: Di Stilio Lab/U of Washington.

The Pink Double Dandy peony, the Double Peppermint petunia, the Doubled Strawberry Vanilla lily and nearly all roses are varieties cultivated for their double flowers. The blossoms of these and other such plants are lush with extra petals in place of the parts of the flower needed for sexual reproduction and seed production, meaning double flowers - though beautiful - are mutants and usually sterile.

The genetic interruption that causes that mutation helped scientists in the 1990s pinpoint the genes responsible for normal development of sexual organs stamens and carpels in the plant Arabidopsis thaliana, long used as a plant model by biologists.

Now for the first time, scientists have proved the same class of genes is at work in a representative of a more ancient plant lineage, offering a glimpse further back into the evolutionary development of flowers.

"It's pretty amazing that Arabidopsis and Thalictrum, the plant we studied, have genes that do the exact same kind of things in spite of the millions of years of evolution that separates the two species," said Veronica Di Stilio, University of Washington associate professor of biology. She is the corresponding author of a paper published in the Proceedings of the National Academy of Sciences.

The function of these organ-identity genes appears to be highly conserved according to the new research, meaning the gene is essential and its function has been maintained despite the formation of new species.

Identifying the genetic and biochemical basis of double flowering in Thalictrum suggests the class of genes that likely underlie other widespread double-flower varieties, according to Kelsey Galimba, a UW doctoral student in the Di Stilio lab and lead author of the paper.

"Growers might be interested that we've figured out what's going on genetically. In terms of applications, you could potentially trigger this if you were interested in creating double flowers because you know which gene to treat to get that flower form," Di Stilio said.

Di Stilio's group studied Thalictrum thalictroides. Known in the nursery trade as Anemonella thalictroides and rue anemone, the spring-flowering plant is native to the woods of Northeastern U.S. It belongs to the family Ranunculaceae, a sister lineage of the Eudicots. Eudicots today include 70 percent of all flowering species.

"The plants we've chosen to study possess ancestral floral traits and are sister to the core Eudicots that have model plants used by biologists such as Arabidopsis thaliana and Antirrhinum majus, or snapdragon," Di Stilio said. "But the plants in our study belong to a more ancient lineage. We're interested in evolution of flowers so we want to look at something that is a little bit different, that might inform us about how development has been tweaked over time to produce change."

The scientists compared the class of genes that direct the development of certain sexual reproduction organs in wild-type Thalictrum with that of the cultivated double-flower version known as Double White.

In the mutant, Galimba spotted part of a transposon, jumping genes that can move about the organism's genome, sitting in the gene that affects development of reproductive organs. The protein produced by the mutant gene lacks some of the amino acids found in wild-type plants and the scientists hypothesize that it's not the right length to interact with other proteins normally, Galimba said.

The researchers then did a second check on the findings by using a technique called viral induced gene silencing to knock down the properly functioning gene in a wild-type plant. The resulting blossom looked very similar to the Double White mutant.

"The flower is one of the key innovations of flowering plants. It allowed flowering plants to coevolve with pollinators - mainly insects, but other animals as well - and use those pollinators for reproduction," Di Stilio said. "Many scientists are interested in finding the genetic underpinnings of flower diversification. Just how flowering plants become so species rich in such a relatively short period of geologic time has been a question since Darwin."

The work was funded by the National Science Foundation, including a research experience for undergraduate fellowship for co-author Theadora Tolkin, now a doctoral student at New York University. Other co-authors are Alessandra Sullivan, former Di Stilio lab member and current UW doctoral student; and collaborators Rainer Melzer and Gunter Theiben with Friedrich Schiller University in Germany. Abstract of PNAS Plus paper

.


Related Links
UW biology department
Explore The Early Earth at TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





EARLY EARTH
Feathered dinosaur feasts on flying food
Edmonton, Canada (SPX) Aug 31, 2012
University of Alberta researchers found evidence that a feathered, but flightless dinosaur was able to snag and consume small flying dinosaurs. The U of A paleontology team found the fossilized remains of three flying dinosaurs in the belly of a raptor-like predator called Sinocalliopteryx. Sinocalliopteryx was about two meters in length and roughly the size of a modern-day wolf. Sinocalli ... read more


EARLY EARTH
NASA's GRAIL Moon Twins Begin Extended Mission Science

Flags at half mast across US for Armstrong funeral

Walls of Lunar Crater May Hold Patchy Ice, LRO Radar Finds

Russia's moonshot hope 'not a dream'

EARLY EARTH
NASA's Mars rover parked to test robotic arm

Curiosity Has a Photo Day

Marks of Laser Exam on Martian Soil

Opportunity Drives And Images Rock Outcrop

EARLY EARTH
Space-age food served up with seeds of success

Africa eyes joint space agency

Africa needs own space agency: Sudan's Bashir

Moles, crabs and Moon dust: DLR at the ILA Space Pavilion

EARLY EARTH
Tiangong Orbit Change Signals Likely Date for Shenzhou 10

China Focus: Timeline for China's space research revealed

China eyes next lunar landing as US scales back

China unveils ambitious space projects

EARLY EARTH
ISS crew complete space station repair

Crew Wraps Up Preparations for Wednesday's Spacewalk

Building MLM Under Way at Khrunichev

Astronauts Complete Second Expedition 32 Spacewalk

EARLY EARTH
First-Stage Fuel Loaded; Launch Weather Forecast Improves

NASA launches mission to explore radiation belts

ISRO to score 100 with a cooperative mission Sep 9

NASA Administrator Announces New Commercial Crew And Cargo Milestones

EARLY EARTH
Birth of a planet

A Hot Potential Habitable Exoplanet around Gliese 163

NASA's Kepler Discovers Multiple Planets Orbiting a Pair of Stars

How Old are the First Planets?

EARLY EARTH
Amazon takes on iPad with new Kindle Fire tablet

US judge OKs partial settlement in e-book case

Empire-style computers? Frenchman takes PCs to lap of luxury

Google-Microsoft field smartphones to take on iPhone 5




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement