GhLTPG1, a cotton GPI-anchored lipid transfer protein, regulates the transport of phosphatidylinositol monophosphates and cotton fiber elongation.
The cotton fibers are seed trichomes that elongate from the ovule epidermis. Polar lipids are required for the quick enlargement of cell membrane and fiber cell growth, however, how lipids are transported from the ovules into the developing fibers remains less known. Here, we reported the functional characterization of GhLTPG1, a GPI-anchored lipid transport protein, during cotton fiber elongation. GhLTPG1 was abundantly expressed in elongating cotton fibers and outer integument of the ovules, and GhLTPG1 protein was located on cell membrane. Biochemical analysis showed that GhLTPG1 specifically bound to phosphatidylinositol mono-phosphates (PtdIns3P, PtdIns4P and PtdIns5P) in vitro and transported PtdInsPs from the synthesis places to the plasma membranes in vivo. Expression of GhLTPG1 in Arabidopsis caused an increased number of trichomes, and fibers in GhLTPG1-knockdown cotton plants exhibited significantly reduced length, decreased polar lipid content, and repression of fiber elongation-related genes expression. These results suggested that GhLTPG1 protein regulates the cotton fiber elongation through mediating the transport of phosphatidylinositol monophosphates.
Plant Biotechnology Research Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Ting
T
Deng
National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology &Ecology, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Hongyan
H
Yao
Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Jin
J
Wang
Plant Biotechnology Research Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Jun
J
Wang
National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology &Ecology, Chinese Academy of Sciences, 300 Fenglin Road, 200032 Shanghai, China.
Hongwei
H
Xue
Plant Biotechnology Research Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Kaijing
K
Zuo
D052179:Antigens, Plant / Q000502:physiology*; D017360:Arabidopsis / Q000254:growth & development; D001692:Biological Transport; D002352:Carrier Proteins / Q000502:physiology*; D032561:Cotton Fiber; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D003368:Gossypium / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D008081:Liposomes; D008563:Membrane Lipids / Q000378:metabolism*; D008565:Membrane Proteins / Q000502:physiology*; D056771:Ovule / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism*; D010940:Plant Proteins / Q000502:physiology*; D018514:Plant Structures / Q000378:metabolism; D011485:Protein Binding; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D018749:RNA, Plant / Q000096:biosynthesis / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013045:Species Specificity; D064201:Trichomes / Q000254:growth & development* / Q000378:metabolism
D052179:Antigens, Plant; D002352:Carrier Proteins; D008081:Liposomes; D008563:Membrane Lipids; D008565:Membrane Proteins; D018129:Phosphatidylinositol Phosphates; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D011993:Recombinant Fusion Proteins; C511920:lipid transfer proteins, plant