Biology and biotechnology of reproduction

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Biology and Biotechnology of Reproduction

Reproductive biology, medicine and biotechnology are important topics of biomedical research. Impaired fertility is an increasing problem both in humans and animals. Assisted reproduction techniques (ART) are routinely applied, but the long-term consequences are only partially understood. Animal models are urgently needed to clarify these questions. Our research projects address the following topics:
Mechanisms of embryo-maternal communication. The establishment and maintenance of pregnancy requires a fine-tuned molecular dialog between the early embryo, and its maternal environment, the uterine endometrium. Within the DFG research unit 478 "Mechanisms of embryo-maternal communication" (Speaker: E. Wolf; www.ematko.de) investigated this cross-talk using holistic transcriptome and proteome studies in the bovine model system. These studies were complemented by the BMBF-funded project Fertilink (Functional genome research for the improvement of fertility; Coordinator: E. Wolf), which investigated estrous cycle-dependent changes in the endometrium in a systematic manner. These studies are now continued in the Junior Group Compendium (Dr. Stefan Bauersachs).
Assisted reproduction techniques (ART).  ART, such as in vitro fertilization (IVF) or intracytoplasmic sperm injection into oocytes (ICSI), are increasingly applied. However, the basic mechanisms underlying these techniques as well as their long-term risks and benefits are incompletely understood. For ethical reasons, such studies are limited in humans. In this context livestock species, particularly the cow, provide excellent model systems.  Within the EU-funded project SABRE (Cutting-edge genomics for sustainable animal production) we investigated long-term effects of ART on epigenetic characteristics of offspring derived by these techniques. In the DFG research unit 1041 "Germ cell potential" we investigate effects of donor age on oocyte developmental potential, using a combination of structural, functional and molecular studies.
Reprogramming and pluripotency. Since Dolly, the cloned sheep, was born in 1996, mechanisms of cellular reprogramming are one of the most prominent fields of biomedical research. Or main interests are epigenetic changes of cloned embryos and offspring. Further, we investigate changes of nuclear architecture during the process of reprogramming in close collaboration with the group of Prof. Thomas Cremer from the LMU BioCenter.
Reproduction and metabolism. Impaired fertility is one of the major reasons for culling of female cattle. There is a clear negative correlation between milk yield and fertility, however the reasons are only partially understood. A "physiological explanation" would be that negative energy balance and the associated metabolic consequences disturb endocrine as well as cellular and molecular functions of the reproductive tissues, leading to impaired fertility. A "genetic explanation" could be that during the efficient selection for fertility traits alleles with a negative effect on fertility were co-selected by linkage disequilibrium or other mechanisms. The BMBF-FUGATO-plus funded project REMEDY- Reproduction and metabolic problems in dairy cows (Coordinator E. Wolf) addresses these questions and attempts to develop parameters for the selection of fertile high-yielding cows.