A mitochondrial phosphate transporter, McPht gene, confers an acclimation regulation of the transgenic rice to phosphorus deficiency
HAN Jiao1, YU Guo-hong2, WANG Li1, LI Wei2, HE Rui3, WANG Bing2, HUANG Sheng-cai2, CHENG Xian-guo2
1 College of Life Science, Shanxi Normal University, Linfen 041000, P.R.China 2 Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, P.R.China 3 College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, P.R.China
Phosphate transporters play an important role in promoting the uptake and transport of phosphate in plants. In this study, the McPht gene from the Mesembryanthemum crystallinum, a mitochondrial phosphate transporter, was isolated and constructed onto a constitutive expression vector carrying 35S::GFP, and the recombinant constructs were transferred into Oryza sativa japonica L. cv. Kitaake to investigate the regulatory role of the McPht gene under phosphorus deficiency. The McPht gene encodes a protein of 357 amino acids with six transmembrane domains and is located to the mitochondria, and the mRNA transcripts of the McPht gene are highly accumulated in the shoots of M. crystallinum in response to phosphorus deficiency. However, more mRNA transcripts of the McPht gene were accumulated in the roots of the transgenic rice under phosphorus deficiency. Measurements showed that the transgenic rice demonstrated an enhanced promotion in the root development, the root activities, and phosphate uptake under phosphorus deficiency. Transcriptome sequencing showed that the transgenic rice exhibited total of 198 differentially expressed genes. Of these, total of 154 differentially expressed genes were up-regulated and total 44 genes were down-regulated comparing to the wild type in response to phosphorus deficiency. The selective six genes of the up-regulated differentially expressed genes showed an enhanced increase in mRNA transcripts in response to phosphorus deficiency, however, the transcripts of the mitochondrial carrier protein transporter in rice, a homologous gene of the McPht, in both the transgenic line and the wild type had no obvious differences. Functional enrichment analyses revealed that the most of the up-regulated genes are involved in the cytoplasmic membrane-bounded vesicle, and most of the down-regulated genes are involved in the mitochondrion and cytoplasmic membrane-bounded vesicle. The differentially expressed genes were highly enriched in plant secondary metabolisms and plant-pathogen interaction. These results indicated that the overexpression of the McPht gene might participate in the physiological adaptive modulation of the transgenic rice to phosphorus deficiency by up- or down-regulating the differentially expressed genes.
Fund: This work was supported by the National Key Project for Cultivation of New Varieties of Genetically Modified Organisms, Ministry of Agriculture, China (2016ZX08002-005), and the National Basic Research Program of China (2015CB150800).
HAN Jiao, YU Guo-hong, WANG Li, LI Wei, HE Rui, WANG Bing, HUANG Sheng-cai, CHENG Xian-guo. 2018. A mitochondrial phosphate transporter, McPht gene, confers an acclimation regulation of the transgenic rice to phosphorus deficiency. Journal of Integrative Agriculture,