Properties of the interaction of Arf-like protein 2 with PDEdelta.
Arf-like proteins (Arl) share certain characteristic features with the Arf subfamily of Ras superfamily proteins, but their function is unknown. Here, we show by a variety of spectroscopic techniques that Arl2, unlike most other Ras-related proteins, has micromolar rather than picomolar affinity for nucleotides. As a consequence of low affinity, nucleotide dissociation rates are rather fast, arguing that it is not regulated by guanine nucleotide exchange factors. Arl2 is isolated as prey in a yeast double hybrid screen using phosphodiesterase 6delta (PDEdelta) as bait. This interaction is dependent on GTP, and the binding of PDEdelta substantially stabilizes GTP binding, increasing affinity and decreasing dissociation rates by a similar factor. Among all Arl proteins tested, PDEdelta only interacted with the closely related proteins Arl2 and Arl3, strongly suggesting that Arl2/3 are specific regulators of PDEdelta.
Max-Planck-Institute for Molecular Physiology, Department of Structural Biology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
Michael
M
Hanzal-Bayer
Marco
M
Linari
Alfred
A
Wittinghofer
D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000378:metabolism*; D020727:ADP-Ribosylation Factors / Q000378:metabolism*; D000818:Animals; D054707:Cyclic Nucleotide Phosphodiesterases, Type 6; D019204:GTP-Binding Proteins / Q000378:metabolism*; D015723:Gene Library; D006160:Guanosine Triphosphate / Q000494:pharmacology; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011485:Protein Binding; D013057:Spectrum Analysis; D020798:Two-Hybrid System Techniques
D008565:Membrane Proteins; D006160:Guanosine Triphosphate; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054707:Cyclic Nucleotide Phosphodiesterases, Type 6; C097313:ADP-ribosylation factor related proteins; C485819:Arl2 protein, mouse; D019204:GTP-Binding Proteins; C490248:Arl3 protein, mouse; D020727:ADP-Ribosylation Factors