The present invention is directed to a polynucleotide sequence of a novel organic anion transporting (OAT)-like protein UST3-likel. More particularly, the present invention provides a polynucleotide sequence comprising the nucleic acid sequence SEQ ID NO: 1 or nucleic acid sequences that hybridize to SEQ ID NO: 1 or its complimentary strand. The invention also provides the human UST3-LIKE1 associated with the gastrointestinal and liver diseases, metabolic diseases, hematological disorders, respiratory diseases, neurological disorders, urological disorders and cardiovascular diseases as a result of relative quantification of the mRNA distribution in different human tissues by expression profiling. The invention also provides assays for the identification of compounds useful for the modulation of said diseases. The methods of the invention involve cell-free and cell-based assays that identify compounds which bind to and/or activate or inhibit the activity of UST3-LIKE1, a organic anion transporting (OAT)-like protein, followed by an in vivo assay of the effect of the compound on said diseases. The invention also features compounds which bind to and/or activate or inhibit the activity of UST3-LIKE1 as well as pharmaceutical compositions comprising such compounds.