1. Isolation and functional characterization of an ammonium transporter gene, PyAMT1, related to nitrogen assimilation in the marine macroalga Pyropia yezoensis (Rhodophyta)
- Author
-
Kazuki Kishi, Hideomi Amano, Chika Nakamoto, Daniel A. Coury, and Makoto Kakinuma
- Subjects
0106 biological sciences ,0301 basic medicine ,Nitrogen ,Nitrogen assimilation ,Mutant ,Aquatic Science ,Biology ,Oceanography ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Ammonium Compounds ,Ammonium ,chemistry.chemical_classification ,General Medicine ,Metabolism ,Pollution ,Amino acid ,Complementation ,Transmembrane domain ,030104 developmental biology ,Biochemistry ,chemistry ,Rhodophyta ,010606 plant biology & botany ,Ammonium transport - Abstract
Ammonium and nitrate are the primary nitrogen sources in natural environments, and are essential for growth and development in photosynthetic eukaryotes. In this study, we report on the isolation and characterization of an ammonium transporter gene (PyAMT1) which performs a key function in nitrogen (N) metabolism of Pyropia yezoensis thalli. The predicted length of PyAMT1 was 483 amino acids (AAs). The AA sequence included 11 putative transmembrane domains and showed approximately 33–44% identity to algal and plant AMT1 AA sequences. Functional complementation in an AMT-defective yeast mutant indicated that PyAMT1 mediated ammonium transport across the plasma membrane. Expression analysis showed that the PyAMT1 mRNA level was strongly induced by N-deficiency, and was more highly suppressed by resupply of inorganic-N than organic-N. These results suggest that PyAMT1 plays important roles in the ammonium transport system, and is highly regulated in response to external/internal N-status.
- Published
- 2017
- Full Text
- View/download PDF