title: TSAd interacts with Smad2 and Smad3.
abstract: Smad-dependent signalling initiated by TGFbeta superfamily members can be modulated by a variety of interacting proteins. Using yeast two-hybrid, co-immunoprecipitation, and GST pull-down assays we identified T-cell SH2 adapter (TSAd) as a protein that interacts with Smad2 and Smad3. TSAd is an adapter protein thought to participate in many different signalling pathways. The objective of this study was to elucidate the domains important for interaction between TSAd and Smad proteins. Our results suggest a model for TSAd-Smad interaction that is facilitated by multiple TSAd domains, but primarily through the TSAd type I SH2 domain. Interestingly, we also found that both Smad2 and Smad3 interact with the Lck type I SH2 domain, but not the PI3K type III SH2 domain. This research raises the possibility that interaction between SH2-containing proteins and Smad proteins may represent another method to modulate Smad-dependent signalling.
authors.affiliation: Department of Pharmacology, Dalhousie University, Halifax, NS, Canada.
authors.forename: K C
authors.initials: KC
authors.lastname: Richard
authors.forename: G E
authors.initials: GE
authors.lastname: Bertolesi
authors.forename: L D
authors.initials: LD
authors.lastname: Dunfield
authors.forename: C R
authors.initials: CR
authors.lastname: McMaster
authors.forename: M W
authors.initials: MW
authors.lastname: Nachtigal
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism*; D001665:Binding Sites; D011485:Protein Binding; D025941:Protein Interaction Mapping; D015398:Signal Transduction / Q000502:physiology*; D051899:Smad2 Protein / Q000737:chemistry* / Q000378:metabolism*; D051900:Smad3 Protein / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C402726:Sh2d2a protein, mouse; D051899:Smad2 Protein; D051900:Smad3 Protein