Arabidopsis Serine Decarboxylase Mutants Implicate the Roles of Ethanolamine in Plant Growth and Development

Abstract

Abstract:Ethanolamine is important for synthesis of choline, phosphatidylethanolamine (PE) and phosphatidylcholine (PC) in plants. The latter two phospholipids are the major phospholipids in eukaryotic membranes. In plants, ethanolamine is mainly synthesized directly from serine by serine decarboxylase. Serine decarboxylase is unique to plants and was previously shown to have highly specific activity to L-serine. While serine decarboxylase was biochemically characterized, its functions and importance in plants were not biologically elucidated due to the lack of serine decarboxylase mutants. Here we characterized an Arabidopsis mutant defective in serine decarboxylase, named atsdc-1 (Arabidopsis thaliana serine decarboxylase-1). The atsdc-1 mutants showed necrotic lesions in leaves, multiple inflorescences, sterility in flower, and early flowering in short day conditions. These defects were rescued by ethanolamine application to atsdc-1, suggesting the roles of ethanolamine as well as serine decarboxylase in plant development. In addition, molecular analysis of serine decarboxylase suggests that Arabidopsis serine decarboxylase is cytosol-localized and expressed in all tissue.

Relationships of Leaf Net Photosynthesis, Stomatal Conductance, and Mesophyll Conductance to Primary Metabolism: A Multispecies Meta-Analysis Approach

“…Additionally, these sugars might prevent cellular dehydration by deep insertion between lipid layers (Van den Ende, 2013). Ethanolamine is a known precursor of phosphatidylethanolamine and phosphatidylcholine, both major phospholipids in eukaryotic membranes (Kwon et al, 2012). Membrane properties and composition directly affect their permeability to solutes, water, and protons, potentially affecting protein membrane activities (Burgos et al, 2011).…”

The Choline/Ethanolamine Kinase Family in Arabidopsis: Essential Role of CEK4 in Phospholipid Biosynthesis and Embryo Development

“…The embryo lethality of cek4-1/+ may be due to a deficiency in phospholipid biosynthesis because mutation in PECT, which catalyzes the reaction following CEK, affects PtdEtn biosynthesis and results in an embryo-lethal phenotype (Mizoi et al, 2006). Moreover, a null mutation in SDC may be lethal (Kwon et al, 2012). Furthermore, mutation in the gene encoding lysophosphatidic acid acyltransferase1 (LPAAT1/ATS2), a key enzyme in de novo glycerolipid biosynthesis (Kennedy pathway), results in an embryo-lethal phenotype (Kim and Huang, 2004;Yu et al, 2004).…”

“…In addition, knocking out of PMT1 (or PEAMT1, XPL1) reduces PtdCho levels slightly (CruzRamírez et al, 2004). Furthermore, a leaky mutant of SDC showed a severe growth defect, which suggests that SDC knockout is lethal (Kwon et al, 2012). Therefore, P-Etn synthesis may be crucial for the biosynthesis of PtdCho and PtdEtn.…”

Mechanism of plant growth promotion elicited byBacillussp. LKE15 in oriental melon

“…LKE15-induced chlorophyll and phosphoserine production could be used to increase the serine content of oriental melon plants. The decarboxylation of serine produces ethanolamine, which is involved in several physiological process including inflorescence development, floral fertility, and flowering (Kwon et al 2012). Hao et al (2004) reported that the external application of a cysteine-derived amino acid, taurine, increased wheat seedling growth.…”