The sensory control of nematocyst development and discharge

• Applicant: Professor Dr. Suat Özbek
• Subject Area: Evolutionary Cell and Developmental Biology (Zoology) ; Animal Physiology and Biochemistry
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 390770057

The nematocyst is the defining feature of the cnidarian clade and represents one of the most complex organelles in the animal kingdom. In previous funding periods, we established the Hydra nematocyst proteome and analyzed the functional and evolutionary aspects of several proteins involved in capsule assembly. Our work has focused on factors that either serve as structural components of the capsule wall and tubule or contribute to its formation through interactions with cytoskeletal elements. In the proposed project, we aim to uncover a previously unrecognized role of Trp ion channels in nematocyst morphogenesis. While the sensory regulation of nematocyte discharge has been investigated, the contribution of ion channel activity to nematocyst development remains entirely unexplored. To address this gap, we have generated new experimental tools, including specific antibodies and transgenic Hydra lines, and identified novel candidate factors that provide the foundation for characterizing Trp ion channel function during nematocyst assembly, both structurally and functionally. Furthermore, we will elucidate the molecular composition and architecture of the cnidocil complex using an integrative approach that combines proteomics, cryo-electron tomography, and functional assays. Together, these studies will provide new insights into nematocyst development and function, as well as the evolutionary origins of mechanosensation in early metazoans.

• DFG Programme: Research Grants