Protein function prediction involves the computational prediction of Proteins. Source information may come from homologous sequences, protein structures, or text mining of publications. Because of the strong link between a protein's structure and function, protein function prediction is similar to Protein structure prediction, with a key difference being that protein function prediction methods may use structural information about the target. One example of a simple protein function prediction method is, given the target protein sequence, do a BLAST search to find the protein with highest sequence similarity with functional annotation, and then transfer that annotation to the target protein.