Identification and Verification of Plant Transcription Factors That Play a Role in Regulating the Production of Triacylglycerol

Triacylglycerols (TAG) play vital roles in plant development and are also utilized by humans for consumption, chemical and industrial feed stocks, and production of biofuels. Their primary function in plants is as an energy reserve stored in seeds to allow for the growth of the developing plant after germination. While many plants accumulate significant quantities of TAGs in the developing embryo or other parts of the seed, significant quantities of TAG accumulation also occurs in nonseed tissues such as the mesocarp of avocado and oil palm, the roots of nutsedge, and the fruits of bay berry. In Arabidopsis the transcription factor Wrinkled 1 (WRI1) was shown to be responsible for regulating the accumulation of TAG in seeds, and homologues of WRI1 have been shown to have similar functions in other plants and plant tissues. However, WRI1 likely does not act alone to control the synthesis and accumulation of TAG in plants. This project aims to identify additional transcription factors that are responsible for controlling the synthesis and accumulation of TAG in nonseed tissues by utilizing transcriptome data from a variety of plant species. The transcriptome data also revealed three homologues of WRI1 that are highly expressed in Avocado mesocarp. Their function in Avocado will be determined by complementing Arabidopsis wri1 mutants and examining TAG accumulation in the resulting transgenic plants. This study is aimed at identifying genes that play a role in the accumulation of high levels of TAG in various plant tissues and confirming the function of the WRI homologues in Avocado. Future studies will be able to use this information to better understand regulation of TAG accumulation in plants which will allow increased oil accumulation and yield in plants for various commercial and industrial applications