Thesis defense: Garry Duville

Studies of NLP transcription factors:
Roles and mechanisms of the NLP-dependent nitrate signaling pathway

Abstract
One of the best-characterized molecular events triggered by nitrate is the primary nitrate response (PNR). This is a rapid and specific process in which the expression of more than 1,000 genes is regulated by a large number of transcription factors to varying degrees. It has already been shown that NLP7 is a key regulator of PNR and that its intracellular localization is regulated by a nuclear accumulation mechanism depending on the presence/absence of nitrate. The objective of my thesis project is to further investigate the function of NLP transcription factors in the transcriptional regulation of nitrate-responsive genes and their impact on plant responses to nitrate availability in the A. thaliana model plant. The first part of my thesis project consisted in determining which protein(s) interacted specifically with NLP7 and what their roles were in the NLP7-dependent nitrate signaling pathway.
Using protein-protein interaction approaches, three candidate proteins have been previously identified as potential NLP7 interactors. Among them is a nucleoporin (NUP) primarily involved in the transport of protein and RNA molecules across the nuclear envelope. My results suggest that the NUP is involved in the nitrate-dependent nuclear accumulation process of NLPs, which may ultimately affect their activity.
The second part of my thesis project focused on less studied NLPs. Indeed, apart from NLP2, NLP6, NLP7, and NLP8, little information is available in the literature on the function of other NLPs in nitrate signaling in Arabidopsis thaliana. My results contribute to improve our understanding of NLP function, although further studies are needed to fully elucidate the molecular mechanisms behind NLP activity in Arabidopsis thaliana.
Arabidopsis thaliana.

Supevisor: Anne Krapp - INRAE, IJPB, Versailles 
Co-supervisor: Zsolt Kelemen - INRAE, IJPB, Versailles


Members of the jury
> Christophe Tatout (Referee) - Université Clermont Auvergne, GReD, Clermont-Ferrand
> Anis Limami (Referee) - Université d'Angers, IRHS, Beaucouzé
> Fernanda De Carvalho-Niebel (Examinator) - Université de Toulouse, LIPME, Castanet Tolosan
> Hoai-Nam Truong-Cellier (Examinator) – INRAE, Institut Agro, Agroécologie, Dijon


To attend, contact Anne Krapp

¹ press release INRAE 8/2/23, news IJPB