Overexpression of PdDUF231A Improves Cellulose Biosynthesis in Poplar

The function of Domain of Unknown Function 231-containing proteins (DUF231) is largely unknown. While previous studies have suggested that DUF231 proteins are related in O-acetyl substitution of hemicellulose and esterification of pectin, little is known about their function in woody plants. A study from Oak Ridge National Laboratory has revealed that one member of the DUF231 proteins in poplar (Populus deltoides), PdDUF231A, is involved in the acetylation of xylan and affects cellulose biosynthesis.

A total of 52 DUF231 proteins were identified in the poplar genome. In transgenic poplar lines overexpressing PdDUF231A, the research team from ORNL found that glucose and cellulose contents were increased, as well as the levels of cellulose synthesis-related genes. Further analysis revealed that total acetylated xylan was increased in the transgenic lines, leading to higher rate of glucose release. Plant biomass productivity was also increased in the transgenic lines.

PdDUF231A could be a promising target for genetic modification for biofuel production since biomass productivity and quality can both be improved through its overexpression.