Abstract: The present invention relates to a cellular screening method for the identification of modulators of secretases. Said method comprises contacting suitable host cells with a test substance wherein said suitable host cells comprise: a) a fusion protein secretory protein, a membrane anchor domain and a secrease cleavage sequence, b) a protein comprising a secretase activity recognising said cleavage sequence of said fusion protein and a) at least one reporter gene under control of a transcriptional activation system wherein said transcriptional activation system is regulated by the release of said secretory protein from said fusion protein by said secretase activity and its subsequent secretion then culturing said cells under suitable conditions such that said reporter gene allowing detection and/or survival of cells is only expressed or repressed in a manner that is dependent on an altered secretase activity due to said test substance.
Type:
Application
Filed:
April 18, 2002
Publication date:
March 30, 2006
Applicant:
ESBATech AG
Inventors:
Alcide Barberis, Oliver Middendorp, Urs Luthi
Abstract: The properties of yeast help, a type I ER membrane protein which is involved in the unfolded protein response (UPR), have been exploited to develop รข. system for the detection and study of interactions between extracellular and/or membrane proteins. In the system, proteins of interest are fused to the lumenal N-terminus of a truncated Ire1p. A specific interaction between two partners may be visualized through dimerization of the Ire1p moiety which, either, directly or indirectly, results in a detection means, for example, the expression of a selectable reporter gene. Depending on the type of reporter gene used, its expression can positively or negatively influence cell growth, thus allowing selection of both stimulation and inhibition of protein-protein interactions. The system presented here can also be used to study intracellular protein interactions.
Type:
Application
Filed:
May 21, 2003
Publication date:
January 26, 2006
Applicant:
ESBATech AG
Inventors:
David Urech, Peter Lichtlen, Alcide Barberis
Abstract: An in vivo method for the identification and/or validation of receptor tyrosine kinase inhibitors is described. Said method is characterised by the following steps: providing host cells comprising a nucleic acid construct encoding a peptide which comprises a tyrosine kinase domain of a receptor tyrosine kinase wherein said peptide lacks a transmembrane domain or a functional fragment thereof and said tyrosine kinase activity in the cytoplasma leads to proliferation arrest, contacting said host cells with a candidate compound and identification of inhibitors of said tyrosine kinase activity by cultivation of said host cells under suitable conditions such that the modulation of the tyrosine kinase activity by the candidate compound leads to cell growth.
Abstract: The present invention concerns a screening system for screening effector peptides that can act as agonists or antagonists, as well as means to produce such a screening system, in particular a specific DNA library encoding peptides. In order to perform the screening, host cells comprising a selection system are transformed with the DNA library and the thus obtained screening system is then cultivated under conditions selectively allowing survival of cells with desired interaction.