Abstract

Plants evolve to adapt to environmental stresses, including changes at the genetic and molecular levels. For bioengineers to utilize genetic manipulation to build tolerance into crops, a better understanding of the mechanism is needed. Published studies have demonstrated that 14-3-3 Lambda (14-3-3 Lambda) protein affect the phenylpropanoid (Pp) biosynthetic pathway and alters production of flavonoids and downstream compounds of importance for stress tolerance. The 14-3-3 family of proteins binds to many different client proteins and serves as signaling scaffolds. In this study 14-3-3 Lambda knockout mutants were used to investigate changes in metabolite accumulation in the downstream Pp pathway. Amongst them are anthocyanins which are important antioxidants involved in a variety of plant functions including stress response. Investigating how drought stress influenced anthocyanin production identified nodes in the Pp pathway affected by 14-3-3 Lambda. A metabolomics analysis employing high resolution mass spectrometry (HRMS) and metabolomics software was used to identify metabolites in 14-3-3 knockout which changed relative to wild-type A. thaliana (Columbia-0) during drought stress. The metabolites Cy-3-p-coumaurolysinapoylsophoroside-5-diglucoside, 3-caffeoylferuloylsophoroside- 5-succinoylglucoside, 3-caffeoylferuloylsophoroside-5-malonyldiglucoside, 3-feruloylsophoroside-5-succinoyl glucoside, petunidin-3,5-O-diglucoside and malvidin-3-O-p-coumarylmonoglucoside show significant differences in their profiles ranging from 18- to > 500-fold between the Col-0 and 14-3-3 Lambda knockout in wet and dry groups. The findings suggest that 14-3-3 Lambda interacts along the CHS, and CHI nodes, which in turn regulate the downstream production of specific anthocyanins. The interaction of 14-3-3 Lambda with CHS was confirmed using co-immunoprecipitation and co-localization studies. This study supports the hypothesis that manipulation of gene expression of 14-3-3 Lambda can lead to development of drought tolerance in plants.

This work is licensed under a Creative Commons Attribution 4.0 License.