Intrinsic and extrinsic regulators of Aux/IAA protein degradation dynamics. Issue 10 (October 2022)

• Record Type: Journal Article
• Authors: Figueiredo, Marcelo Rodrigues Alves de; Strader, Lucia C.
• Is Part Of: Trends in biochemical sciences. Volume 47:Issue 10(2022)
• Page Start: 865
• Page End: 874
• Publication Date: 2022-10
• Subjects: auxin -- intrinsically disorder regions -- SLiM -- binding context -- degron; Biochemistry -- Periodicals; 572
• DOI: 10.1016/j.tibs.2022.06.004
• Languages: English
• ISSNs: 0968-0004

Abstract

Abstract : The plant hormone auxin acts through regulated degradation of Auxin/INDOLE-3-ACETIC ACID (Aux/IAA) proteins to regulate transcriptional events. In this review, we examine the composition and function of each Aux/IAA structural motif. We then focus on recent characterization of Aux/IAA N-terminal disordered regions, formation of secondary structure within these disordered regions, and post-translational modifications (PTMs) that affect Aux/IAA function and stability. We propose how structural variations between Aux/IAA family members may be tuned for differential transcriptional repression and degradation dynamics. Highlights: Auxin controls many aspects of plant growth and development by regulating the degradation of short-lived Auxin/INDOLE-3-ACETIC ACID INDUCIBLE (Aux/IAA) transcriptional repressors. Advances in protein structural biology are allowing detailed characterization of the nonglobular and intrinsically disordered N-terminal portions of Aux/IAA proteins, revealing how amino acid composition and post-translational modifications (PTMs) of the N terminus are essential for regulated proteolysis. Motif- and context-based interactions of the N termini of Aux/IAA proteins regulate interactions with TIR1/AFB auxin co-receptors and also with ubiquitin ligase receptors.