Regulatory function of Arabidopsis lipid transfer protein 1 (LTP1) in ethylene response and signaling.
Ethylene as a gaseous plant hormone is directly involved in various processes during plant growth and development. Much is known regarding the ethylene receptors and regulatory factors in the ethylene signal transduction pathway. In Arabidopsis thaliana, REVERSION-TO-ETHYLENE SENSITIVITY1 (RTE1) can interact with and positively regulates the ethylene receptor ETHYLENE RESPONSE1 (ETR1). In this study we report the identification and characterization of an RTE1-interacting protein, a putative Arabidopsis lipid transfer protein 1 (LTP1) of unknown function. Through bimolecular fluorescence complementation, a direct molecular interaction between LTP1 and RTE1 was verified in planta. Analysis of an LTP1-GFP fusion in transgenic plants and plasmolysis experiments revealed that LTP1 is localized to the cytoplasm. Analysis of ethylene responses showed that the ltp1 knockout is hypersensitive to 1-aminocyclopropanecarboxylic acid (ACC), while LTP1 overexpression confers insensitivity. Analysis of double mutants etr1-2 ltp1 and rte1-3 ltp1 demonstrates a regulatory function of LTP1 in ethylene receptor signaling through the molecular association with RTE1. This study uncovers a novel function of Arabidopsis LTP1 in the regulation of ethylene response and signaling.
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Honglin
H
Wang
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Yue
Y
Sun
Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA.
Jianhong
J
Chang
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Fangfang
F
Zheng
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Haixia
H
Pei
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Yanjun
Y
Yi
Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA. carenc@umd.edu.
Caren
C
Chang
College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China. chunhai79@yahoo.com.
Chun-Hai
CH
Dong
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D005030:Ethylenes / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D009154:Mutation / Q000235:genetics; D030821:Plants, Genetically Modified; D011485:Protein Binding; D021381:Protein Transport; D015398:Signal Transduction; D013347:Subcellular Fractions / Q000378:metabolism
D029681:Arabidopsis Proteins; D005030:Ethylenes; C036216:ethylene
Arabidopsis; ETR1 receptor; Ethylene signaling; Lipid transfer protein 1 (LTP1); RTE1