Compositions and methods for enhancing the resistance of plants to pests and for altering the level of biotin in plants are provided. Nucleotide sequences isolated from soybean, rice, maize, and wheat are provided. The nucleotide sequences encode orthologs of sunflower SCIP-1. Also provided are the SCIP-1 proteins encoded by such nucleotide sequences. The methods involve transforming plants with the SCIP-1 nucleotide sequences to enhance the plant's resistance to plant pests or to alter the level of biotin in the plant. Transformed plants, plant cells, tissues, and seeds are also provided.