The developmental dynamics of the maize leaf transcriptome

Nov 03, 2010

Photosynthesis is arguably the most impressive feat of nature, where plants harvest light energy and convert it into the building blocks of life at fantastically high efficiency. Indeed modern civilization became possible only with the cultivation of plants for food, shelter and clothing.

While scientists have been able to discover details of the fascinating process by which plants store solar energy as , how developing plants build and regulate their solar reactors is still poorly understood. How many genes are involved, and which are the most important? How are different cell types endowed with specific biochemical capacities? What signals fine-tune how much sugar is produced, and which bioproducts are generated? The answers to these questions have applications in agriculture, bioenergy and climate change.

Complex and multifaceted questions such as these can be addressed using a new approach to measure using high throughput sequencing. This method, coined RNAseq, is detailed in a new report from scientists at the Boyce Thompson Institute for Plant Research (BTI) and Cornell University published online in the journal . The study, using the agronomically critical maize (corn) plant as a model, tracks through massive sequencing of gene transcripts, the full complement of expressed genes in a corn leaf. The researchers found that as the leaf develops, entire suites of genes are turned on and off. "Previous studies have often focused on understanding one gene or set of genes that underpin a specific pathway or process", notes Tom Brutnell, an associate scientist at the BTI and the senior author of the study, "However, these new tools have let us examine the expression of all genes in the leaf at very specific stages of development. This provides an unprecedented view of the genetic circuitry of the leaf."

While such results are exciting, they also pose big challenges as scientists work to interpret the datasets. In this study, over 25,000 genes were found to be expressed in each leaf, and nearly half of these are transcribed into at least two different forms, called splicing variants. To make sense out of this flood of information, scientists at BTI, Cornell, Yale, Iowa State and the University of Toronto collaborated to develop systems biology tools that combine computational and statistical methods to analyze large datasets. "The interface between developmental biologists, molecular biologists, and computer scientists that made this work possible, is an excellent example of why systems biology is able to unravel complex biological pathways" commented David Stern, President of BTI.

An important aspect of this work is that it provides insight into the regulation of the unusual form of photosynthesis that maize utilizes referred to as C4 that increases water and nitrogen use efficiencies under hot dry environments. "Some of the most productive food, feed and bioenergy crops utilize C4 photosynthesis including maize, sugarcane and the grass Miscanthus", notes Brutnell "This study provides the first comprehensive analysis of gene expression in any C4 plant and thus provides the groundwork for a genetic dissection of this process".

Given the economic importance of C4 plant in the United States and around the world, these findings have numerous potential applications to agriculture. Optimizing photosynthetic capacity could not only enhance the performance of maize, but also enable far-reaching transformations of photosynthesis in species which are currently far less efficient than maize, such as rice or wheat.

Explore further: Mosses survive climate catastrophes

Provided by Boyce Thompson Institute for Plant Research

not rated yet
add to favorites email to friend print save as pdf

Related Stories

Key discovered to cold tolerance in corn

Aug 29, 2008

Demand for corn -- the world's number one feed grain and a staple food for many -- is outstripping supply, resulting in large price increases that are forecast to continue over the next several years. If corn's intolerance ...

Plant gene for water efficiency found

Jul 11, 2005

ANU researchers have identified a gene that regulates the water efficiency of plants, the first to be discovered that mediates the process critical to plant survival, crop yield and vegetation dynamics. Dr Josette Masle, fro ...

How to build a plant

Jun 26, 2008

Dr. Sarah Hake and her colleagues, George Chuck, Hector Candela-Anton, Nathalie Bolduc, Jihyun Moon, Devin O'Connor, China Lunde, and Beth Thompson, have taken advantage of the information from sequenced grass genomes to ...

Rice yields researched to tackle food security issues

Jun 21, 2010

A pioneering project in the Philippines, which aims to develop a new, higher-yielding rice plant which could ease the threat of hunger for the poor, is being led by an academic at the University of Sheffield.

Recommended for you

'Most famous wheat gene' found

10 hours ago

Washington State University researchers have found "the most famous wheat gene," a reproductive traffic cop of sorts that can be used to transfer valuable genes from other plants to wheat.

Mosses survive climate catastrophes

16 hours ago

Mosses have existed on Earth for more than 400 million years. During this period they survived many climate catastrophes that wiped out more robust organisms such as, for example, dinosaurs. Recently, British ...

Final pieces to the circadian clock puzzle found

Sep 14, 2014

Researchers at the UNC School of Medicine have discovered how two genes – Period and Cryptochrome – keep the circadian clocks in all human cells in time and in proper rhythm with the 24-hour day, as well ...

Measuring modified protein structures

Sep 14, 2014

Swiss researchers have developed a new approach to measure proteins with structures that change. This could enable new diagnostic tools for the early recognition of neurodegenerative diseases to be developed.

User comments : 0