Abstract: A method for selecting a peptide or polypeptide which binds to a target is provided. The method is based on protein splicing and phage display.

Abstract: The invention concerns a method for random mutagenesis comprising the replication of a DNA sequence in the presence of an efficient amount of at least a mutase, for example a Pol ?, the random mutagenesis rate being at least of the order of 1 mutation for 400 base pairs. The replication product, optionally recombined and amplified, is cloned in an expression vector so as to generate mutated polypeptides which will be selected on the basis of the desired property or properties.

Abstract: The present invention provides an in vitro method for obtaining a library of polynucleotides encoding antibodies, derivatives thereof or fragments thereof, comprising the step of performing random mutagenesis of a polynucleotide encoding the variable region of a heavy chain and/or the variable region of a light chain of a light chain, wherein random mutagenesis is performed on a library of polynucleotides comprising a sequence encoding the variable region of a heavy chain and/or the variable region of a light chain; and wherein the random mutagenesis process creates randomly distributed mutations along at least 70% of the sequence encoding the variable region.

Abstract: This invention relates to an expression cassette for expressing polypeptides in eukaryotic cells using alternative splicing. The expression cassette comprises in 5? to 3? downstream direction: a promoter; a sequence transcribed in a 5? untranslated region (5?UTR); a donor splice site; an intron; a first acceptor splice site; a first cistron encoding a first polypeptide; a second acceptor splice site; a second cistron encoding a second polypeptide; an internal ribosome entry site (IRES) operably linked to a selection marker; and a sequence transcribed in a 3? untranslated region (3?UTR) including a polyadenylation signal, wherein the polyadenylation signal is unique.

Abstract: The present invention provides a versatile and sensitive method for studying interaction of two peptides or polypeptides A and B within the cytoplasm of a host cell. The method is based on the use of two distinct chimeric polypeptides. The first chimeric polypeptide containing an aggregation domain fused to a polypeptide A and the second one containing a phenotype-associated functional domain fused to a second polypeptide B. When these chimeric polypeptides are co-expressed within a host cell allowing aggregation of the aggregation domain, the phenotype of the host cell depends on the entrapment of the phenotype-associated functional domain which only occurs when A and B interact with each other.