β-Trefoil structure enables interactions between lectins and protease inhibitors that regulate their biological functions.
Fungal ricin B-like lectins and protease inhibitors, mycocypins and mycospins, are important mediators in fungal defence against antagonists and all possess the β-trefoil fold. We demonstrate here that fungal β-trefoil proteins interact with each other, in addition to their apparent targets, and that these interactions modulate their biological activity. Such regulation of carbohydrate binding or inhibitory activity is observed for the first time in β-trefoil proteins and could constitute a mechanism for regulating their physiological functions. It could also have implications in molecular recognition of other combinations of β-trefoil proteins in other species.
Department of Biotechnology, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; and Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia.
Simon
S
Žurga
Department of Biotechnology, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; and Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia.
Jure
J
Pohleven
Department of Biotechnology, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; and Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia Department of Biotechnology, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; and Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia.
Janko
J
Kos
Department of Biotechnology, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; and Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, SI-1000 Ljubljana, Slovenia jerica.sabotic@ijs.si.
Jerica
J
Sabotič
D000363:Agaricales / Q000737:chemistry; D037102:Lectins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011480:Protease Inhibitors / Q000737:chemistry* / Q000378:metabolism; D017510:Protein Folding; D000071164:Trefoil Factor-2
D037102:Lectins; D010455:Peptides; D011480:Protease Inhibitors; D000071164:Trefoil Factor-2
R-type domain; interaction; protease inhibitor; ricin B-like lectin; β-trefoil fold