Overexpression of AtAGT1 promoted root growth and development during seedling establishment
Arabidopsis photorespiratory gene AtAGT1 is important for the growth and development of root, the non-photosynthetic organ, and it is involved in a complex metabolic network and salt resistance.
AtAGT1 in Arabidopsis encodes an aminotransferase that has a wide range of donor:acceptor combinations, including Asn:glyoxylate. Although it is one of the photorespiratory genes, its encoding protein has been suggested to function also in roots to metabolize Asn. However, experimental data are still lacking. In this study, we investigated experimentally the function of AtAGT1 in roots and our results uncovered its importance in root development during seedling establishment after seed germination. Overexpression of AtAGT1 in roots promoted both the growth of primary root and outgrowth of lateral roots. To further elucidate the molecular mechanisms underlying, amino acid content and gene expression in roots were analyzed, and results revealed that AtAGT1 is involved in a complex metabolic network and salt resistance of roots.
KeywordsAtAGT1 Seedling establishment Asn Ser Salt tolerance ABA signaling
We thank Prof. Hermann Bauwe and Dr. Stefan Timm, Rostock University, for giving us valuable suggestions in preparing this article and providing us transgenic Arabidopsis lines with leaf-specific expression of FpSGT. We also wish to thank Prof. Ningning Wang, Nankai University, for providing us the Arabidopsis PRP3 promoter. This work was supported by National Natural Science Foundation of China (Grant no. 31270296), PPP Project of CSC-DAAD (2013) and 111 Project B08011.
Author contribution statement
YW designed the experiments; RW, LY, LZ, YZ and XH performed experiments; BX, YZ and YB contributed to technical support, discussion of the experiments and manuscript; YW, RW and XH wrote this MS.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interest.
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