Random PCR-based screening for soluble domains using green fluorescent protein

A novel approach to screen soluble protein domains is presented, by combini ng tagged random primer polymerase chain reaction (PCR) method and protein- folding assay using green fluorescent protein. Tagged random primer PCR met hod was used to amplify random DNA fragments from a template cDNA The PCR p roducts were fused to the green fluorescent protein (GFP) gene. Then solubi lities of their translation products were rapidly monitored by the fluoresc ence of transformed Escherichia coli colonies on plates. We succeeded in cl oning four soluble domains from Vav protein using this method. The present method is applicable to all proteins when cDNAs are available. (C) 2001 Aca demic Press.