Model Based on Crystallography of Histone mRNA Stem-Loop with Exonuclease and SLBP (image) University of North Carolina Health Care Share Print E-Mail Caption This shows the structure of Histone mRNA stem-loop (center) with the proteins exonuclease (left) and SLBP (right). Arrow (top center) points to the twist. Credit Tong lab, Columbia University and Marzluff lab, UNC School of Medicine Usage Restrictions None Share Print E-Mail 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.