ABCG9, ABCG11 and ABCG14 ABC transporters are required for vascular development in Arabidopsis

Abstract

SUMMARYIn order to obtain insights into the regulatory pathways controlling phloem development, we characterized three genes encoding membrane proteins from the G sub-family of ABC transporters (ABCG9, ABCG11 and ABCG14), whose expression in the phloem has been confirmed. Mutations in the genes encoding these dimerizing 'half transporters' are semi-dominant and result in vascular patterning defects in cotyledons and the floral stem. Co-immunoprecipitation and bimolecular fluorescence complementation experiments demonstrated that these proteins dimerize, either by flexible pairing (ABCG11 and ABCG9) or by forming strict heterodimers (ABCG14). In addition, metabolome analyses and measurement of sterol ester contents in the mutants suggested that ABCG9, ABCG11 and ABCG14 are involved in lipid/sterol homeostasis regulation. Our results show that these three ABCG genes are required for proper vascular development in Arabidopsis thaliana.

ChIP-Seq reveals that QsMYB1 directly targets genes involved in lignin and suberin biosynthesis pathways in cork oak (Quercus suber)

“…Because homo- and heterodimers of ABCG11 and ABCG12 are reported as important for wax export and ABCG13 seems to be required for cutin deposition in flowers [ 67 ], it is widely accepted that tissue-dependent combinations of different half-size ABCG proteins involved in the transport of wax, cutin and suberin components are possible to occur [ 61 ]. Furthermore, ABCG11 can form dimers with ABCG9 and ABCG14 which links it to a function in lipid homeostasis regulation in vascular organs as phloem [ 68 ]. Additionally, a recent study reported that half-size ABCG2, ABCG6 and ABCG20 are involved in the formation of suberin layers in seed coats and roots where abcg2/6/20 triple mutants had increased permeability, altered suberin structure and reduce aliphatic components [ 69 ].…”

Whole-Transcriptome Survey of the Putative ATP-Binding Cassette (ABC) Transporter Family Genes in the Latex-Producing Laticifers of Hevea brasiliensis

“…A. thaliana AtABCG25 and AtABCG40 are involved in abscisic acid (ABA) transport and responses [ 68 , 69 ]. Recent studies have indicated that ABCG9, ABCG11 and ABCG14 are involved in lipid/sterol homeostasis regulation, which is required for proper vascular development in A. thaliana [ 70 ]. Finally, some members of ABCG subfamily confer plant resistance to various biotic and abiotic stresses [ 71 , 72 ].…”

Metabolic Engineering of the Native Monoterpene Pathway in Spearmint for Production of Heterologous Monoterpenes Reveals Complex Metabolism and Pathway Interactions

“…Additionally, in animal system a co-regulation of fatty acid production and sterol biosynthesis is observed for proper maintenance of cell membranes during cellular growth [ 55 , 56 ]. Studies in Arabidopsis sterol biosynthetic mutants have also revealed changes in fatty acid composition indicating a link between sterol and fatty acid metabolism [ 57 , 58 , 59 ]. The changes in fatty acid esters is solely due to increase in flux into fatty acid biosynthesis upon monoterpene pathway inhibition or increase in sterols also has an impact on FA metabolism remains to be deciphered.…”