Conventional Model Versus Proposed Model (IMAGE) University of California - Riverside Caption UC Riverside researchers have received funding from the W. M. Keck Foundation to conduct research aimed at showing that membrane transporters guide steroid hormones into cells (right panel), challenging a long-standing paradigm in endocrinology that simple diffusion is solely responsible for such transport (left panel). A membrane transporter lodged within the cell membrane is shown in green. Steroid hormones are depicted by orange circles. Credit Haga-Yamanaka lab, UC Riverside. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.