TY - JOUR

T1 - Developmental and hormonal regulation of Arabidopsis thaliana ornithine-delta-aminotransferase

AU - Egorova, A. A.

AU - Gerasimova, S. V.

AU - Kochetov, A. V.

N1 - We thank Vera Gorelova for help in conducting the experiments and writing the manuscript. The work is supported by the Ministry of Science and Higher Education of Russian Federation (FWNR-2022-0017). Publisher Copyright: © 2022 Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences. All rights reserved.

PY - 2022/3

Y1 - 2022/3

N2 - Ornithine aminotransferase (OAT) catalyzes transfer of the delta-amino group from L-ornithine to oxo-glutarate. In plants, this reaction biochemically connects urea cycle, proline cycle, and polyamine biosynthesis pathway. OAT activity is shown to be associated with biotic and abiotic stress responses and nitrogen metabolism, but its physiological role is still unclear. In our study, we decided to investigate transcriptional regulation of the OAT gene in Arabidopsis thaliana under normal conditions and in response to various growth regulators. In the present work, the reporter gene construct containing the Escherichia coli β-glucuronidase gene (gus) under control of the A. thaliana OAT gene promoter was introduced into the genome of A. thaliana ecotype Columbia plants using the floral dip method; GUS activity was assayed in different experimental conditions including hormone treatment, low and high nitrogen and salinity. The GUS activity was analyzed histochemically. Plants were incubated with staining solution containing X-Gluc. We show that under standard growth conditions, the promoter is active during germination and in developing floral organs. OAT promoter activity specifically activates in response to different forms of auxin (IAA, NAA, and 2,4D), cytokinin (6-BAP), ethylene precursor (ACC), high nitrogen and salinity. Analysis of the OAT expression by qRT-PCR confirmed the pattern observed using the GUS reporter system. The OAT gene showed a significantly elevated expression in four-day-old seedlings and in plant roots in response to auxins and cytokinins. The analysis of the OAT promoter structure reveals cis-acting regulatory DNA elements associated with auxin regulation and abiotic stresses. The results of the study indicate that the OAT gene is involved in developmental processes and is regulated by auxin and cytokinins.

AB - Ornithine aminotransferase (OAT) catalyzes transfer of the delta-amino group from L-ornithine to oxo-glutarate. In plants, this reaction biochemically connects urea cycle, proline cycle, and polyamine biosynthesis pathway. OAT activity is shown to be associated with biotic and abiotic stress responses and nitrogen metabolism, but its physiological role is still unclear. In our study, we decided to investigate transcriptional regulation of the OAT gene in Arabidopsis thaliana under normal conditions and in response to various growth regulators. In the present work, the reporter gene construct containing the Escherichia coli β-glucuronidase gene (gus) under control of the A. thaliana OAT gene promoter was introduced into the genome of A. thaliana ecotype Columbia plants using the floral dip method; GUS activity was assayed in different experimental conditions including hormone treatment, low and high nitrogen and salinity. The GUS activity was analyzed histochemically. Plants were incubated with staining solution containing X-Gluc. We show that under standard growth conditions, the promoter is active during germination and in developing floral organs. OAT promoter activity specifically activates in response to different forms of auxin (IAA, NAA, and 2,4D), cytokinin (6-BAP), ethylene precursor (ACC), high nitrogen and salinity. Analysis of the OAT expression by qRT-PCR confirmed the pattern observed using the GUS reporter system. The OAT gene showed a significantly elevated expression in four-day-old seedlings and in plant roots in response to auxins and cytokinins. The analysis of the OAT promoter structure reveals cis-acting regulatory DNA elements associated with auxin regulation and abiotic stresses. The results of the study indicate that the OAT gene is involved in developmental processes and is regulated by auxin and cytokinins.

KW - Arabidopsis thaliana

KW - auxin

KW - development

KW - nitrogen

KW - ornithine aminotransferase

KW - Arabidopsis thaliana

KW - auxin

KW - development

KW - nitrogen

KW - ornithine aminotransferase

UR - http://www.scopus.com/inward/record.url?scp=85133058477&partnerID=8YFLogxK

UR - https://elibrary.ru/item.asp?id=48203265

UR - https://www.mendeley.com/catalogue/a2af7f3e-2af5-321b-acaa-54ada3ea4161/

U2 - 10.18699/VJGB-22-19

DO - 10.18699/VJGB-22-19

M3 - Article

C2 - 35434486

AN - SCOPUS:85133058477

VL - 26

SP - 153

EP - 158

JO - Вавиловский журнал генетики и селекции

JF - Вавиловский журнал генетики и селекции

SN - 2500-0462

IS - 2

M1 - 5

ER -