Salt cress genome yields new clues to salt tolerance

Jul 13, 2012

An international team, led by Institute of Genetics and Developmental Biology, Chinese Academy of Science, and BGI, the world's largest genomics organization, has completed the genomic sequence and analysis of salt cress (Thellungiella salsuginea), a wild salt-tolerant plant. The salt cress genome serves as a useful tool for exploring mechanisms of adaptive evolution and sheds new lights on understanding the genetic characteristics underlying plant abiotic stress tolerance. The study was published online in PNAS.

Salt Cress is a typical halophyte with high resistance to cold, drought, oxidative stresses and salinity. Due to its small plant size, short life cycle, copious seed production, small , and an efficient transformation, salt cress could serve as an important system for botanist, geneticists, and breeders to better explore the of abiotic stress tolerance.

In the study, researchers sequenced the genome of salt cress (Shandong ecotype) using the paired-end Solexa sequencing technology. The genomic data yielded a of salt cress with about 134-fold coverage. The final length of the assembled sequences amounted to about 233.7 Mb, covering about 90% of the estimated size (~260 Mb). A total of 28,457 protein-coding regions were predicted in the sequenced salt cress genome. Researchers found that the average exon length of salt cress and A. thaliana genes was similar, whereas the average intron length of salt cress was about 30% larger than that of A. thaliana.

The evolutionary analysis indicated that salt cress and its close relative- - diverged from approximately 7 -12million years ago. When tracing the differences between salt cress and A. thaliana, researchers found salt cress was characterized by a dramatically different lifestyle, a unique gene complement, significant differences in the expression of orthologs, and a larger genome size. Noticeably, the salt cress genome showed a dramatically higher content of transposable elements (TEs) than that of A. thaliana, which may be the reason for its enlarged genome size. In common with other higher plants, salt cress genome was consisted of abundance of long terminal repeat (LTR) retrotransposons.

Salt can have drastic effects on the growth and yield of agronomical crops. It is estimated that salinity renders about one-third of the world's irrigated land unsuitable for crop production. In this study, researchers identified many genes in salt cress that contribute to its success in high-salt environments, such as the genes related with cation transport, abscisic acid signaling, and wax production.

Junyi Wang, Director of Science & Technology, Research & Cooperation Center, BGI, said, "Salt cress provides an excellent model and opportunity for researchers to explore plant's mechanisms of abiotic stress tolerance. The completed genomic sequence of salt cress will boost the advancement of research as well as provide a valuable theoretic instruct and technical support for researchers worldwide to better face the challenges of the soil salinization in irrigation area, the development and utilization of shallow offshore waters and beaches, and food security."

Explore further: Small doses of resistant starch encourage the growth of beneficial gut fauna

More information: http://www.pnas.org/content/early/2012/07/05/1209954109.abstract?sid=548ade97-58d5-4c0a-a1e4-e1a43a9c9c21

add to favorites email to friend print save as pdf

Related Stories

Evolution can cause a rapid reduction in genome size

Apr 21, 2011

(PhysOrg.com) -- It would appear reasonable to assume that two closely related plant species would have similar genetic blueprints. However, scientists from the Max Planck Institute for Developmental Biology ...

Sequencing thousand and one genomes

Sep 29, 2008

(PhysOrg.com) -- Researchers at the Max Planck Institute for Developmental Biology in Tuebingen, Germany, reported the completion of the first genomes of wild strains of the flowering plant Arabidopsis thaliana. ...

FANCM plays key role in inheritance

Apr 30, 2012

Scientists of KIT and the University of Birmingham have identified relevant new functions of a gene that plays a crucial role in Fanconi anemia, a life-threatening disease.

Salt-tolerant gene found in simple plant nothing to sneeze at

Apr 07, 2008

Whether a plant withers unproductively or thrives in salty conditions may now be better understood by biologists. The cellular mechanism that controls salt tolerance has been found in the arabidopsis plant by a Texas AgriLife ...

Salt production started in ancient China

Aug 23, 2005

A Harvard University study reports large-scale salt production occurred in inland China more than 2,000 years ago, the earliest date yet uncovered.

Recommended for you

Solving the Hox Specificity Paradox

Jan 22, 2015

The remarkable diversity of anatomical features along the body axis of animals—the differences between the head, the thorax and the abdomen, for example—is determined by proteins in the Hox family. But ...

The Facebook of plant science

Jan 21, 2015

By building PhotosynQ - a handheld device with sensors and an online data-sharing and analysis platform - a team of Michigan State University researchers is creating the plant-science equivalent of Facebook.

New computation method helps identify functional DNA

Jan 21, 2015

Striving to unravel and comprehend DNA's biological significance, Cornell scientists have created a new computational method that can identify positions in the human genome that play a role in the proper ...

User comments : 0

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.