Novel GDSL-type esterase

A novel GDSL-type esterase, SFAR4 was found in Arabidopsis thaliana. In this study, knockout mutants and overexpression lines were established. The absence and overexpression of the SFAR4 gene had no effect on germination rate when compared with the wild-types. However, in the presence of glucose, the lines with overexpressed SFAR4 had significantly higher germination rates than wild-type and knockout mutants. In contrast, the presence of mannitol did not affect germination rates. This finding suggests that perhaps SFAR4, a GDSL-type esterase plays a role in glucose susceptibility and glucose metabolic pathway regulation in germinating seeds. In this same study, the expression of fatty acid metabolic genes are shown to be differential in SFAR4 overexpression lines and knockout mutants. SFAR4 overexpression lines show increases levels of metabolism pathway components while knockout mutant lines are accompanied by lower levels of fatty acid metabolism gene expression. This indicates that SFAR4 plays a role in fatty acid metabolism.