Laboratory of Molecular Biology
In 1965 he joined the staff of the MRC Laboratory of Molecular Biology and then became Programme Leader. He was visiting professor in biochemistry and molecular biology at Harvard University (1974–75) and Eleanor Roosevelt Cancer Society Fellow and visiting professor, Stanford University (1984–85). He was head of the cell biology division, MRC Laboratory of Molecular Biology at the University of Cambridge (1986-1995) and was elected a Fellow of the Royal Society in 1985. Mark was Emeritus scientist from 2005-2013. He was the first to demonstrate the existence of oriented transmembrane proteins.