Aux/IAA

Description

Tiwari et al. (2004): Aux/IAA proteins are short-lived nuclear proteins that repress expression of primary/early auxin response genes in protoplast transfection assays. Repression is thought to result from Aux/IAA proteins dimerizing with auxin response factor (ARF) transcriptional activators that reside on auxin-responsive promoter elements, referred to as AuxREs. Most Aux/IAA proteins contain four conserved domains, designated domains I, II, III, and IV. Domain II and domains III and IV play roles in protein stability and dimerization, respectively. A clear function for domain I had not been established. Results reported here indicate that domain I in Aux/IAA proteins is an active repression domain that is transferable and dominant over activation domains. An LxLxL motif within domain I is important for conferring repression. The dominance of Aux/IAA repression domains over activation domains in ARF transcriptional activators provides a plausible explanation for the repression of auxin response genes via ARF-Aux/IAA dimerization on auxin-responsive promoters.

References:


1) Liscum, E; Reed, JW. 2002. Genetics of Aux/IAA and ARF action in plant growth and development. Plant Mol. Biol. 49(3-4):387-400 PubMed
2) Tiwari, SB; Hagen, G; Guilfoyle, TJ. 2004. Aux/IAA proteins contain a potent transcriptional repression domain. Plant Cell 16(2):533-43 PubMed
3) Tiwari, SB; Wang, XJ; Hagen, G; Guilfoyle, TJ. 2001. AUX/IAA proteins are active repressors, and their stability and activity are modulated by auxin. Plant Cell 13(12):2809-22 PubMed


Summary

Name: Aux/IAA
Class: TR
Number of species containing the TAP: 94
Number of available proteins: 2821

The colour code corresponds to the rules for the domains:

should be contained
should not be contained

Domain rules:


(Domain names are clickable)


Phylogenetic tree for Archeaplastida:

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TAP distribution:

The following table shows the distribution of Aux/IAA over all species included in TAPscan. The values for e.g. a specific kingdom are shown in the tree below if you expand the tree for that kingdom.

Minimum Maximum Average Median Standard deviation
09523.992618.18

List of species containing Aux/IAA sorted by kingdomcladesupergrouporderfamily:

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expand kingdom Archaeplastida (2855 proteins in 94 species)