Lamin A vs. Lamin B (image) University of Pennsylvania Caption The nuclear envelope around DNA has a lamin mesh that is less phosphorylated and more stable under high stress, regulating gene expression. Credit Joe Swift and Irena Ivanovska, University of Pennsylvania Usage Restrictions With Credit. 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.