Since SFPQ-TFE3 expression is limited to PAX8-expressing cells in the STP model due to use of the Pax8-CreERT model, this model serves as a lineage tracing experiment, thereby substantiating renal tubular epithelial cells as the cell of origin for a TFE3 fusion-driven murine PEComa model. The gene discussed is TFE3; the disease is neoplasm with perivascular epithelioid cell differentiation.