Richard Zimmermann is Professor of Biochemistry and Molecular Biology at the Medical School of Saarland University, Homburg, Germany. His research interests fall within the fields of intracellular protein transport and molecular chaperones, with an emphasis on the role of chaperones and co-chaperones in protein transport into the mammalian endoplasmic reticulum. He received his PhD from the “Georg-August”-University in Gottingen, Germany, and was Postdoc at the Molecular Biology Institute of the University of California at Los Angeles, USA. Before his current appointment he was Assistant Professor at the “Ludwig-Maximilians”-University in Munich and Associate Professor at the “Georg-August”-University o f Gottingen, both Germany. Since 2005 he heads the Competence Center for Molecular Medicine at Saarland University (KoMM).

• Preface 1. Post-Targeting Function s of Signal Peptides 2 . mRNA Translation on the Endoplasmic Reticulum: Kinetic Advantages to Protein Synthesis on the E R .3. Translocon Organization in Cells 4 . Structure of the Sec61 – Complex 5. Sec C o m p lex es in the Yeast ER 6. The Role of BiP and Its Co -Chaperones 7 Membrane Protein Biosynthesis at the Endoplasmic Reticulum 8 . Membrane Insertion of Tail-Anchored Proteins. 9. Human Pathologies of Protein Transport into the Endoplasmic Reticulum