OsHSD1, a hydroxysteroid dehydrogenase, is involved in cuticle formation and lipid homeostasis in rice.
Cuticular wax, a hydrophobic layer on the surface of all aerial plant organs, has essential roles in plant growth and survival under various environments. Here we report a wax-deficient rice mutant oshsd1 with reduced epicuticular wax crystals and thicker cuticle membrane. Quantification of the wax components and fatty acids showed elevated levels of very-long-chain fatty acids (VLCFAs) and accumulation of soluble fatty acids in the leaves of the oshsd1 mutant. We determined the causative gene OsHSD1, a member of the short-chain dehydrogenase reductase family, through map-based cloning. It was ubiquitously expressed and responded to cold stress and exogenous treatments with NaCl or brassinosteroid analogs. Transient expression of OsHSD1-tagged green fluorescent protein revealed that OsHSD1 localized to both oil bodies and endoplasmic reticulum (ER). Dehydrogenase activity assays demonstrated that OsHSD1 was an NAD(+)/NADP(+)-dependent sterol dehydrogenase. Furthermore, OsHSD1 mutation resulted in faster protein degradation, but had no effect on the dehydrogenase activity. Together, our data indicated that OsHSD1 plays a specialized role in cuticle formation and lipid homeostasis, probably by mediating sterol signaling. This work provides new insights into oil-body associated proteins involved in wax and lipid metabolism.
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Zhe
Z
Zhang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Zhi-Jun
ZJ
Cheng
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Lu
L
Gan
National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, PR China.
Huan
H
Zhang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Fu-Qing
FQ
Wu
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Qi-Bing
QB
Lin
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Jiu-Lin
JL
Wang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Jie
J
Wang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Xiu-Ping
XP
Guo
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Xin
X
Zhang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Zhi-Chao
ZC
Zhao
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Cai-Lin
CL
Lei
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Shan-Shan
SS
Zhu
National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, PR China.
Chun-Ming
CM
Wang
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; National Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, PR China. Electronic address: wanjianmin@caas.cn.
Jian-Min
JM
Wan
D002874:Chromosome Mapping; D003001:Cloning, Molecular; D006913:Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D050356:Lipid Metabolism / Q000235:genetics*; D012275:Oryza / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D010940:Plant Proteins; D006913:Hydroxysteroid Dehydrogenases
Cuticular wax; Hydroxysteroid dehydrogenase; Lipid; Oil body; Oryza sativa