Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Phox/Bem1p (PB1) domains are universal structural modules that use surfaces of different charge for protein-protein association. In plants, PB1-mediated interactions of auxin response factors (ARF) and auxin/indole 3-acetic acid inducible proteins regulate transcriptional events modulated by the phytohormone auxin. Here we investigate the thermodynamic and structural basis for Arabidopsis thaliana ARF7 PB1 domain self-interaction. Isothermal titration calorimetry and NMR experiments indicate that key residues on both the basic and acidic faces of the PB1 domain contribute to and organize coordinately to stabilize protein-protein interactions. Calorimetric analysis of ARF7PB1 site-directed mutants defines a two-pronged electrostatic interaction. The canonical PB1 interaction between a lysine and a cluster of acidic residues provides one prong with an arginine and a second cluster of acidic residues defining the other prong. Evolutionary conservation of this core recognition feature and other co-varying interface sequences allows for versatile PB1-mediated interactions in auxin signaling.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4432302PMC
http://dx.doi.org/10.1074/jbc.M115.648253DOI Listing

Publication Analysis

Top Keywords

pb1-mediated interactions
8
interactions auxin
8
pb1 domain
8
cluster acidic
8
acidic residues
8
pb1
5
defining two-pronged
4
two-pronged structural
4
structural model
4
model pb1
4

Similar Publications

Nodule Inception (NIN) and NIN-like protein 1 (NLP1), both belonging to the RWP-RK type transcription factors, play critical roles in plant development. Specifically, NIN is pivotal in facilitating root nodule symbiosis in nitrogen-starved conditions, while NLP1 coordinates nodulation in response to nitrate level. In this study, we conducted domain swapping experiments between NIN and NLP1 in Medicago truncatula to elucidate the functional significance of their respective domains.

View Article and Find Full Text PDF

Phox/Bem1p (PB1) domains are universal structural modules that use surfaces of different charge for protein-protein association. In plants, PB1-mediated interactions of auxin response factors (ARF) and auxin/indole 3-acetic acid inducible proteins regulate transcriptional events modulated by the phytohormone auxin. Here we investigate the thermodynamic and structural basis for Arabidopsis thaliana ARF7 PB1 domain self-interaction.

View Article and Find Full Text PDF

Panicle blast 1 (Pb1) is a panicle blast resistance gene derived from the indica rice cultivar "Modan." Pb1 encodes a coiled-coil-nucleotide-binding site-leucine-rich repeat (CC-NB-LRR) protein and confers durable, broad-spectrum resistance to Magnaporthe oryzae races. Here, we investigated the molecular mechanisms underlying Pb1-mediated blast resistance.

View Article and Find Full Text PDF

Nbr1, a ubiquitous kinase scaffold protein, contains a PB1, and a ubiquitin-associated (UBA) domain. We show here that the nbr1 UBA domain binds to lysine-48 and -63 linked polyubiquitin-B chains. Nbr1 also binds to the autophagic effector protein LC3-A via a novel binding site.

View Article and Find Full Text PDF

The superoxide-producing phagocyte NADPH oxidase is activated during phagocytosis to destroy ingested microbes. The adaptor protein p40phox associates via the PB1 domain with the essential oxidase activator p67phox, and is considered to function by recruiting p67phox to phagosomes; in this process, the PX domain of p40phox binds to phosphatidylinositol 3-phosphate [PtdIns(3)P], a lipid abundant in the phagosomal membrane. Here we show that the PtdIns(3)P-binding activity of p40phox is normally inhibited by the PB1 domain both in vivo and in vitro.

View Article and Find Full Text PDF