Catalysis of the transfer of a mannose residue from GDP-mannose to an oligosaccharide, forming an alpha-1,3-linkage [goid 33] [pmid 12684507] [evidence IDA]; Interacting selectively with a protein C-terminus, the end of any peptide chain at which the 1-carboxy function of a constituent amino acid is not attached in peptide linkage to another amino-acid residue [goid 8022] [pmid 14999017] [evidence IPI]; Catalysis of the transfer of a glycosyl group from one compound (donor) to another (acceptor) [goid 16757] [evidence IEA]; Interacting selectively with both a protein or protein complex and a membrane, in order to maintain the localization of the protein at a specific location on the membrane [goid 43495] [pmid 16957052] [evidence IMP]; Interacting selectively with a nonidentical protein to form a heterodimer [goid 46982] [pmid 11278427] [evidence IPI]; Interacting selectively with a protein N-terminus, the end of any peptide chain at which the 2-amino (or 2-imino) function of a constituent amino acid is not attached in peptide linkage to another amino-acid residue [goid 47485] [pmid 12445460] [evidence IPI]; Interacting selectively with a protein N-terminus, the end of any peptide chain at which the 2-amino (or 2-imino) function of a constituent amino acid is not attached in peptide linkage to another amino-acid residue [goid 47485] [pmid 11883939] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 12445460] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 11883939] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 14999017] [evidence IMP]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 17045351] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 16957052] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 17196169] [evidence IPI]; Interacting selectively with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules), in the presence of calcium [goid 48306] [pmid 12445460] [evidence IPI]