Glutamate Transporter Associated Proteins and nucleotide encoding Glutamate Transporter Associated Proteins are provided. Also provided is a method for identifying a compound that modulates a cellular response mediated by a Glutamate Transporter Associated Protein. A method is further provided for identifying a compound that inhibits an interaction between a Glutamate Transporter Associated Protein and a glutamate transporter protein. A method is provided for treating a disorder associated with glutamate transport.