alsheimer lab

The defining characteristic of eukaryotes is the sequestration of the genetic material by the nuclear envelope (NE). The NE is composed of two nuclear membranes, nuclear pore complexes and the nuclear lamina, a proteinaceous meshwork that is in intimate contact with the nuclear side of the inner nuclear membrane. Besides its primary role in separating nuclear and cytoplasmic activities, the NE constitutes a most central component of intracellular architecture. It is vitally involved in many fundamental nuclear functions such as dynamic chromatin organization, transcription and replication. Several components of the NE were identified to function as key players in signalling pathways and recent studies evidenced that the NE has a pivotal role in nuclear migration, anchoring and positioning. Furthermore, the NE was demonstrated to be a most crucial determinant for maintaining nuclear morphology and shape and for general nuclear integrity and, beyond, the NE was shown to serve as a kind of rail for telomere driven chromosomal rearrangement during meiotic prophase I. Thus, from the current point of view the nuclear envelope represents more than just a simple barrier, rather it constitutes a multifunctional platform at the very center of fundamental cellular processes.

Research in our lab covers several aspects regarding the function of the nuclear envelope and its components during dynamic reorganization of nuclei. One main focus is set on the role of the nuclear envelope in the evolutionary highly conserved meiotic chromosome dynamics and its impact on genome haploidization. In a second core project we try to figure out the molecular mechanisms underlying the well-directed nuclear shaping during sperm head formation.

Besides this, we are also engaged in analyzing general mechanisms of meiotic chromosome pairing and synapsis. We for example try to understand the specific function of telomere driven bouquet formation. We also study the molecular composition of synaptonemal complexes (SCs) and the regulation of SC assembly and disassembly. Furthermore, we are interested in evolutionary aspects of meiosis, i.e. the evolution of the synaptonemal complex in metazoans.

Zhang, J., Ruiz, M., Bergh, P.-O., Henricsson, M., Stojanović, N., Devkota, R., Henn, M., Bohlooly-Y, M., Hernández-Hernández, A., Alsheimer, M., Borén, J., Pilon, M., and Shibuya, H. (2024). Regulation of meiotic telomere dynamics through membrane fluidity promoted by AdipoR2-ELOVL2. Nat. Commun. 5, 2315. doi: 10.1038/s41467-024-46718-6

Thoma, H., Grünewald, L., Braune, S., Pasch, E., and Alsheimer, M. (2023). SUN4 is a spermatid type II inner nuclear membrane protein that forms heteromeric assemblies with SUN3 and interacts with lamin B3. J. Cell Sci. 136,  jcs.260155. doi.org/10.1242/jcs.260155

Dedukh, D., da Cruz, I., Kneitz, S., Marta, A., Ormanns, J., Tichopád, T., Lu, Y., Alsheimer, M., Janko, K., and Schartl, M. (2022). Achiasmatic meiosis in the unisexual Amazon molly, Poecilia formosa. Chromosome Res. 30, 443-457.  doi: 10.1007/s10577-022-09708-2.

Nanda, I., Schories, S., Simeonov, I., Adolfi, M.C., Du, K., Steinlein, C., Alsheimer, M., Haaf, T., and Schartl, M. (2022). Evolution of the Degenerated Y-Chromosome of the Swamp Guppy, Micropoecilia picta. Cells 11, 1118. doi: 10.3390/cells11071118

Koncicka, M., Cervenka, J., Jahn, D., Sucha, R., Vodicka, P., Gad, A., Alsheimer, M., and Susor, A. (2020). Expression of lamin C2 in mammalian oocytes. PLoS ONE 15, e0229781. doi: 10.1371/journal.pone.0229781

Gao, Q., Khan, R., Yu, C., Alsheimer, M., Jiang, X., Ma, H., and Shi, Q. (2020). The testis specific LINC component SUN3 is essential for sperm head shaping during mouse spermiogenesis. J. Biol. Chem. 295, 6289-6298.  doi: 10.1074/jbc.RA119.012375

Levy,Y., Ross, J.A., ... , Alsheimer, M. , ... , Lopez-Otin, C., Kennedy, B.K., Lowe, D.A., and Ochala J. (2018). Prelamin A causes aberrant myonuclear arrangement and results in muscle fiber weakness. JCI Insight 3, e120920. doi: 10.1172/jci.insight.120920

Link, J., Paouneskou, D., ... , Alsheimer, M. , Zetka, M., and Jantsch, V. (2018).Transient and partial nuclear lamina disruption promotes chromosome movement in early meiotic prophase. Dev. Cell 45, 212-225. doi: 10.1016/j.devcel.2018.03.018

Link, J., Benavente, R., and Alsheimer, M. (2016). Analysis of Meiotic Telomere Behavior in the Mouse. Methods Mol. Biol. 1411, 195-208. doi: 10.1007/978-1-4939-3530-7_12

Gómez, R., Felipe-Medina, N., Ruiz-Torres, M., Berenguer, I., Viera, A., Pérez, S., Barbero, J.L., Llano, E., Fukuda, T., Alsheimer, M., Pendás, A. M., Losada, A., and Suja, J.A. (2016). Sororin loads to the synaptonemal complex central region independently of meiotic cohesin complexes. EMBO Rep 17, 695-707. doi: 10.15252/embr.201541060

Pasch, E., Link, J., Beck, C., Scheuerle, S., and Alsheimer, M. (2015). The LINC complex component Sun4 plays a crucial role in sperm head formation and fertility. Biol. Open 4, 1792-1802. doi: 10.1242/bio.015768