Arabidopsis inositol 1,3,4-trisphosphate 5/6 kinase 2 is required for seed coat development  

作　　者：Yong Tang Shutang Tan Hongwei Xue 

机构地区：[1]National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences, Shanghai 200032, China

出　　处：《Acta Biochimica et Biophysica Sinica》2013年第7期549-560,共12页生物化学与生物物理学报（英文版）

基　　金：We thank Prof Hongquan Yang （Shanghai Jiao Tong University, Shanghai, China） for providing the axr2-1 mutant seeds and Wenli Hu for help in analyzing the lipid polyesters by GC-MS.The study was supported by a grant from the National Science Foundation of China （No. 31130060）.

摘　　要：Inositol 1,3,4-trisphosphate 5/6 kinase （ITPK） phosphory-lates inositol 1,3,4-trisphosphate to form inositol 1,3,4,5-tetrakisphosphate and inositol 1,3,4,6-tetrakisphosphate which can be finally transferred to inositol hexaphosphate （IP6） and play important roles during plant growth and development. There are 4 putative ITPK members in Arabidopsis. Expression pattern analysis showed that ITPK2 is constitutively expressed in various tissues. A T- DNA knockout mutant of ITPK2 was identified and scan- ning electron microscopy （SEM） analysis showed that the epidermis structure of seed coat was irregularly formed in seeds of itpk2-1 mutant, resulting in the increased perme- ability of seed coat to tetrazolium salts. Further analysis by gas chromatography coupled with mass spectrometry of lipid polyester monomers in cell wall confirmed a dra- matic decrease in composition of suberin and cutin, which relate to the permeability of seed coat and the formation of which is accompanied with seed coat development. These results indicate that ITPK2 plays an essential role in seed coat development and lipid polyester barrier formation.Inositol 1,3,4-trisphosphate 5/6 kinase （ITPK） phosphory-lates inositol 1,3,4-trisphosphate to form inositol 1,3,4,5-tetrakisphosphate and inositol 1,3,4,6-tetrakisphosphate which can be finally transferred to inositol hexaphosphate （IP6） and play important roles during plant growth and development. There are 4 putative ITPK members in Arabidopsis. Expression pattern analysis showed that ITPK2 is constitutively expressed in various tissues. A T- DNA knockout mutant of ITPK2 was identified and scan- ning electron microscopy （SEM） analysis showed that the epidermis structure of seed coat was irregularly formed in seeds of itpk2-1 mutant, resulting in the increased perme- ability of seed coat to tetrazolium salts. Further analysis by gas chromatography coupled with mass spectrometry of lipid polyester monomers in cell wall confirmed a dra- matic decrease in composition of suberin and cutin, which relate to the permeability of seed coat and the formation of which is accompanied with seed coat development. These results indicate that ITPK2 plays an essential role in seed coat development and lipid polyester barrier formation.

关 键 词：Arabidopsis thaliana inositol 1 3 4-trisphosphate 5/6 kinase （ITPK） seed coat SUBERIN CUTIN 

分 类 号：Q943[生物学—植物学] TS201.2[轻工技术与工程—食品科学]