Conformational features of signal sequences and folding of secretory proteins in yeasts

A yeast secretion system has been used extensively for the production of eukaryotic proteins that are expressed as non-native aggregates in E. coli. Secretory proteins translocate through the membrane using signal sequences, and fold in the cells (probably with the aid of several molecular chaperones). In combination with recent techniques of mutagenesis, this system has recently been implemented to study structure/function in signal sequences, and in vivo folding mechanisms of proteins. This review focuses on approaches to conformational features of signal sequences and folding of secretory proteins in yeasts.