A tonoplast intrinsic protein in Gardenia jasminoides

2nd International Conference on Materials Science, Energy Technology and Environmental Engineering

材料科学;能源学;生态环境科学

Gao, Lan^1 ; Li, Hao-Ming^1

School of Basic Courses, Guangdong Pharmaceutical University, Guangzhou Higher Education Mega Center, Guangzhou

510006, China^1

关键词: Arabidopsis thaliana;    Fruit maturation;    Membrane spanning;    Phylogenetic analysis;    Plasma membrane intrinsic proteins;    Three-dimensional model;    Tonoplast intrinsic proteins;    Transcript level;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/81/1/012039/pdf
DOI  :  10.1088/1755-1315/81/1/012039

来源: IOP

【 摘 要 】

Physiological and molecular studies proved that plasma membrane intrinsic proteins (PIPs) and tonoplast intrinsic proteins (TIPs) subfamily of aquaporins play key functions in plant water homeostasis. Five specialized subgroups (TIP1-5) of TIPs have been found in higher plants, in which the TIP1 and TIP2 isoforms are the largest arbitrary groups. TIPs have high water-transport activity than PIPs, some TIPs can transport other small molecule such as urea, ammonia, hydrogen peroxide, and carbon dioxide. In this work, the structure of the putative tonoplast aquaporin from Gardenia jasminoides (GjTIP) was analyzed. Its transcript level has increased during fruit maturation. A phylogenetic analysis indicates that the protein belongs to TIP1 subfamily. A three-dimensional model structure of GjTIP was built based on crystal structure of an ammonia-permeable AtTIP2-1 from Arabidopsis thaliana. The model structure displayed as a homo-tetramer, each monomer has six trans-membrane and two half-membrane-spanning α helices. The data suggests that the GjTIP has tendency to be a mixed function aquaporin, might involve in water, urea and hydrogen peroxide transport, and the gating machanism founded in some AQPs involving pH and phosphorylation response have not been proved in GjTIP.