CO2 response screen in grass Brachypodium reveals the key role of a MAP kinase in CO2-triggered stomatal closure.

Plants respond to increased CO2 concentrations through stomatal closure, which can contribute to increased water use efficiency. Grasses display faster stomatal responses than eudicots due to dumbbell-shaped guard cells flanked by subsidiary cells working in opposition. However, forward genetic screening for stomatal CO2 signal transduction mutants in grasses has yet to be reported.

Globulins are the main seed storage proteins in Brachypodium distachyon.

Brachypodium distachyon is being developed as a model system to study temperate cereals and forage grasses. We have begun to investigate its utility to understand seed development and grain filling by identifying the major seed storage proteins in a diploid accession Bd21. With the use of ID SDS-PAGE and mass spectrometry we detected seven major storage protein bands, six of which were identified as globulins.

Transcriptional profiling of wheat caryopsis development using cDNA microarrays.

The expression of 7,835 genes in developing wheat caryopses was analyzed using cDNA arrays. Using a mixed model analysis of variance (ANOVA) method, 29% (2,237) of the genes on the array were identified to be differentially expressed at the 6 different time-points examined, which covers the developmental stages from coenocytic endosperm to physiological maturity. Comparison of genes differentially expressed between two time-points revealed a dynamic transcript accumulation profile with major re-programming events that occur at 3-7, 7-14 and 21-28 DPA.

Analysis of the wheat endosperm transcriptome.

Among the cereals, wheat is the most widely grown geographically and is part of the staple diet in much of the world. Understanding how the cereal endosperm develops and functions will help generate better tools to manipulate grain qualities important to end-users. We used a genomics approach to identify and characterize genes that are expressed in the wheat endosperm.