Genes for Improved Wood Quality

 

Princiapl Investigator

Gary Peter

University of Florida

Co-Investigators

Matias Kirst

University of Florida

Agency

CPBR/DOE/Arborgen

3 Years
Project Overview:

The primary challenge for breeders and biotechnologists is to increase the productivity and value of southern pine trees by improving the quality of wood and fibers while accelerating stem growth rates.  To help meet this challenge molecular biologists are beginning to identify the genes, alleles and molecular mechanisms that control stem growth rates and the properties of wood and fibers. The development of wood, which is secondary xylem, has been studied at the tissue level, but not at the level of specific cells.  The primary goal of the proposed research project is to study secondary xylem development at the cell level.  We propose to determine which genes are expressed at specific stages of secondary xylem development and in specific cell types to accelerate the discovery and functional analysis of genes that control secondary growth, wood and fiber quality traits.

Our research strategy is to generate gene sequence, gene expression information and cDNA libraries from individual cell types at different stages of secondary xylem development in loblolly pine.  The different cell types, fusiform initials, ray initials, tracheid, ray and resin canal epithelial cells will be captured at various stages of development by laser capture microdissection from cryosections.  The RNA isolated from these captured cells will be amplified and used to hybridize cDNA microarrays to identify which genes on the arrays are expressed in what cell types and at what stages of development.  The amplified RNA will also be used to create cell specific libraries from discrete developmental stages for high throughput sequencing.  High throughput sequencing should permit the isolation of new genes not previously identified in previous EST sequencing efforts, due to their low abundance or lack of representation in the tissue collected.  The knowledge gained from this research will permit the isolation of promoters for more precise developmental and cell specific control of expression for future genetic engineering approaches to improve wood quality traits and will inform the selection of candidate genes for functional testing by association genetics and genetic transformation methods.