Characterization of Novel Secreted and Membrane Proteins Isolated by the Signal Sequence Trap Method

摘要: We recently described a method, called the signal sequence trap (SST) to clone cDNAs of secreted proteins and/or type I transmembrane containing N-terminal sequences by using an epitope-tagging expression plasmid vector. In this paper we describe summary large-scale screening approximately 5900 clones SST cDNA library constructed from mouse bone marrow stromal cell line ST-2 cells. Of 26 positive obtained and sequenced, 11 appeared contain authentic sequences. Five corresponded 5' ends known genes The full-length 6 other unknown were isolated sequenced. One clone, termed SDF3, encoded counterpart human pigment epithelium-derived factor. Another SDR1, had considerable homology with basigin, member immunoglobulin superfamily. A third SDF5, partial Drosophila tissue polarity gene frizzled (fz) its rat homologues, fz-1 fz-2. three no significant in databases. These results indicate that method is effective useful for isolation membrane without knowledge their functions.