AUTHOR=Patnaik Alena , Kumar Aman , Behera Anshuman , Mishra Gayatri , Dehery Subrat Kumar , Panigrahy Madhusmita , Das Anath Bandhu , Panigrahi Kishore C. S. 

TITLE=GIGANTEA supresses wilt disease resistance by down-regulating the jasmonate signaling in Arabidopsis thaliana

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1091644

DOI=10.3389/fpls.2023.1091644

ISSN=1664-462X

ABSTRACT=<p>GIGANTEA (GI) is a plant-specific nuclear protein that plays a pleiotropic role in the growth and development of plants. GI’s involvement in circadian clock function, flowering time regulation, and various types of abiotic stress tolerance has been well documented in recent years. Here, the role of GI in response to <italic>Fusarium oxysporum</italic> (<italic>F. oxysporum</italic>) infection is investigated at the molecular level comparing Col-0 WT with the <italic>gi-100</italic> mutant in <italic>Arabidopsis thaliana</italic>. Disease progression, photosynthetic parameters, and comparative anatomy confirmed that the spread and damage caused by pathogen infection were less severe in <italic>gi-100</italic> than in Col-0 WT plants. <italic>F. oxysporum</italic> infection induces a remarkable accumulation of GI protein. Our report showed that it is not involved in flowering time regulation during <italic>F. oxysporum</italic> infection. Estimation of defense hormone after infection showed that jasmonic acid (JA) level is higher and salicylic acid (SA) level is lower in <italic>gi-100</italic> compared to Col-0 WT. Here, we show that the relative transcript expression of <italic>CORONATINE INSENSITIVE1</italic> (<italic>COI1</italic>) and <italic>PLANT DEFENSIN1.2</italic> (<italic>PDF1.2</italic>) as a marker of the JA pathway is significantly higher while <italic>ISOCHORISMATE SYNTHASE1</italic> (<italic>ICS1</italic>) and <italic>NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1</italic> (<italic>NPR1</italic>), the markers of the SA pathway, are downregulated in the <italic>gi-100</italic> mutants compared to Col-0 plants. The present study convincingly suggests that the GI module promotes susceptibility to <italic>F. oxysporum</italic> infection by inducing the SA pathway and inhibiting JA signaling in <italic>A. thaliana</italic>.</p>