During the past two decades research on the testis has created a vast number of publications. New techniques, such as cell and gene clon ing, germ cell manipulation and transplantation, as well as gene ex pression, have surpassed the classical approaches that involved studies on receptor activation and endocrine, paracrine and autocrine regula tory mechanisms. Due to the expansion of this field of research it has become increasingly difficult to integrate the large number of observa tions and relate them to the physiology and pathophysiology of the tes tis. More emphasis must, therefore, be put on the integration of isolated findings and the construction of the total picture. In order to stimulate this specific mental activity we have named this book Testicular Tan gram. We hope that the chapters in this book will be used as pieces of the testicular puzzle and that the reader enjoys composing new shapes. The chapters of this book are representative of the plenary lectures presented at the I ih European Workshop on Molecular and Cellular Endocrinology of the Testis held in Doorwerth The Netherlands, from April 6 - I 0, 2002. Publication of this book has been made possible by the generous support of the Ernst Schering Research Foundation. We would also like to thank the distinguished scientists, who have pro vided us with their excellent manuscripts well before the start of the Workshop. We acknowledge the help of Dr. U. -F. Habenicht, Dr. M.

1 Multiple Guardians of the Epithelial Stage IV Meiotic Checkpoint

2 Role of Sertoli Cells in Hypospermatogenesis Induced by Antiandrogens
3 Understanding the Mutation-Induced Activation of the Lutropin Receptor from Computer Simulation
4 Sex-Specific Differences in the Control of Mammalian Gametogenesis: Vive la Difference!
5 Cloning and Characterization of Male Germ-Cell-Specific Genes
6 Control of Spermatogenesis via Sertoli Cells
7 Gene-Modified Animal Models for the Study of Luteinizing Hormone and Luteinizing Hormone Receptor Function
8 Analysing Differential Gene Expression in the Testis
9 Spermatogonial Stem Cell Development
10 Multimeric Coactivator Complexes for Steroid/Nuclear Receptors
11 DAX1 and SF1 Mutations Provide Insight Into Sexual Differentiation
Previous Volumes Published in this Series.