Reverse genetics of mucilage synthesis in the Arabidopsis thaliana seed coat

In Arabidopsis, the mucilage secretory cells (MSC) of the seed coat produce a pectinaceous mucilage. Very little is known about which genes are involved in the synthesis of pectins. A reverse genetic approach was used to identify genes involved in mucilage synthesis. A publicly available microarray database was screened with expression visualization tools, and was complemented by in-lab microarray experiments between wild type and known MSC mutants to identify candidate cell wall genes highly expressed at the time of mucilage synthesis. Several cell wall genes were also chosen based on their putative functions which would implicate them in mucilage synthesis. Phenotyping of mutant lines obtained for the cell wall candidate genes revealed no abnormal mucilage phentoypes in single or select double mutant lines. These results indicate that significant genetic redundancy exists in cell wall genes and/or the genes studied do not play significant roles in mucilage synthesis.