<abstract xmlns="http://www.w3.org/1999/xhtml">

Nitrate reductase (NR) and nitrite reductase (NiR) play important roles in nitrate assimilation in plants. Previous studies have indicated that NR and NiR in eelgrass may contribute to its NaCl tolerance. This study investigated the expression characteristics and the biological functions of NR and NiR in eelgrass (<italic>Zostera marina</italic>), named as ZmNR and ZmNiR, were cloned, characterised and overexpressed in both bacteria and tobacco. The open reading frames of ZmNR and ZmNiR contain 2628 and 1773 nucleotides that encode 875 and 590 amino acids respectively. Amino acid sequence alignment indicated that the purported ZmNR and ZmNiR proteins presented low homology with other plant NR and NiR sequences. Real-time quantitative PCR revealed that the expression of ZmNR and ZmNiR was supressed when exposed to low salinity and induced by high salinity. Further physiological analyses demonstrated that blocking nitrate assimilation by adding Na2WO4 in eelgrass reduced its tolerance to NaCl stress. The heterologous expression of the ZmNR and ZmNiR genes in <italic>Escherichia coli</italic> and <italic>Nicotiana benthamiana</italic> could confer tolerance to NaCl stress. Physiological and growth analyses suggested that ZmNR and ZmNiR in plants could resist NaCl stress by regulating various physiological pathways and biochemical processes triggered by nitric oxide (NO). Taken together, these results suggested that NR-dependent NO synthesis may play an important role in NaCl tolerance in eelgrass.
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Nitrate reductase (NR) and nitrite reductase (NiR) play important roles in nitrate assimilation in plants. Previous studies have indicated that NR and NiR in eelgrass may contribute to its NaCl tolerance. This study investigated the expression characteristics and the biological functions of NR and NiR in eelgrass (Zostera marina), named as ZmNR and ZmNiR, were cloned, characterised and overexpressed in both bacteria and tobacco. The open reading frames of ZmNR and ZmNiR contain 2628 and 1773 nucleotides that encode 875 and 590 amino acids respectively. Amino acid sequence alignment indicated that the purported ZmNR and ZmNiR proteins presented low homology with other plant NR and NiR sequences. Real-time quantitative PCR revealed that the expression of ZmNR and ZmNiR was supressed when exposed to low salinity and induced by high salinity. Further physiological analyses demonstrated that blocking nitrate assimilation by adding Na2WO4 in eelgrass reduced its tolerance to NaCl stress. The heterologous expression of the ZmNR and ZmNiR genes in Escherichia coli and Nicotiana benthamiana could confer tolerance to NaCl stress. Physiological and growth analyses suggested that ZmNR and ZmNiR in plants could resist NaCl stress by regulating various physiological pathways and biochemical processes triggered by nitric oxide (NO). Taken together, these results suggested that NR-dependent NO synthesis may play an important role in NaCl tolerance in eelgrass.

Role of Nitrate Reductase and Nitrite Reductase in NaCl Tolerance in Eelgrass (<italic>Zostera marina</italic> L.)

Ecological Chemistry and Engineering S

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Role of Nitrate Reductase and Nitrite Reductase in NaCl Tolerance in Eelgrass ( L.)

Nitrate reductase (NR) and nitrite reductase (NiR) play important roles in nitrate assimilation in plants. Previous studies have indicated that NR and NiR in...

Role of Nitrate Reductase and Nitrite Reductase in NaCl Tolerance in Eelgrass (Zostera marina L.)

Published Online: Apr 22, 2022

Page range: 111 - 125

DOI: https://doi.org/10.2478/eces-2022-0010

Keywords
heterologous expression, nitrate assimilation, NaCl tolerance,

© 2022 Xinfang Lv et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Supplementary Material Details

Role of Nitrate Reductase and Nitrite Reductase in NaCl Tolerance in Eelgrass (Zostera marina L.)

Published Online: Apr 22, 2022

Page range: 111 - 125

DOI: https://doi.org/10.2478/eces-2022-0010

Keywordsheterologous expression, nitrate assimilation, NaCl tolerance,

© 2022 Xinfang Lv et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Supplementary Material Details

Keywords
heterologous expression, nitrate assimilation, NaCl tolerance,