Identification and expression of genes involved in the arabinoxylan biosynthetic pathway in oat

Sammanfattning: Oat is one of the most cultivated cereal crops in the world, and Arabinoxylan (AX) is a dietary fiber in oats with positive health effects. The biosynthetic pathway AX in Oat is still unknown, and which genes are active in its production. Ortholog genes have been identified in oat from other species like rice, wheat, barley, and Arabidopsis. These genes include GT43, GT47, GT61, UAM1, and UAM2. Expression analysis of three oat mutant populations was made in the early, middle, and late developmental stages. Quantifying of AX was also made in the reference oat variety Belinda in 4 different developmental stages. All genes analyzed were expressed in oat with a higher upregulation in the earlier stages except GT61. Accumulation of AX had a similar pattern, suggesting that AX accumulation and gene expression is higher in its first developmental stages. A phylogenetic tree was built using the protein sequences of GT43, GT47, GT61, UAM1, and UAM2 in Arabidopsis thaliana (At), Avena sativa (As), Oryza sativa (Os), Triticum aestivum (Ta), and Hordeum vulgare (Hv) by the maximum likelihood method. The phylogenetic tree showed homology between the genes in the different species. Another phylogenetic tree was also built for the genes identified in oat and showed a clear relation between the genes.