21 September 2026, 11:00
The Key to Life: How the SPARK Complex Unlocks Vertebrate Fertilization
Description AbstractFertilization requires gamete recognition and membrane fusion yet the molecular basis of this process in vertebrates remains unknown We identify SPARK sperm protein assembly and receptor binding key a conserved multi protein complex that integrates all known sperm fertilization factors including TMEM81 IZUMO1 SPACA6 and DCST1 2 together with two newly identified components TMDD1 and FAM187A SPARK subunits are mutually dependent for stability in mature sperm and disruption of any single component causes male sterility in zebrafish and mice Incubating zebrafish sperm with soluble egg receptor Bouncer partially rescues fertilization of Bouncer deficient eggs in a SPARK dependent manner consistent with egg receptor binding priming the complex for fusion Thus we propose SPARK as a con served molecular machine that couples gamete recognition to membrane fusion Connection detailsZoom https www google com url q https embl org zoom us j 94328842098 pwd fkFpTwL3dGati0RDZxaqjv4waJXcrf 1 jst 2 sa D source calendar ust 1789544319644714 usg AOvVaw2NP4zguJ2 780CkO2gzj8e Meeting ID 94328842098 Password 855080 Please note that the talk will yes not be recorded For the FAQ section as a zoom participant please use either the chat function the host will read out your question or the raise your hand function and turn on your microphone... AbstractFertilization requires gamete recognition and membrane fusion, yet the molecular basis of this process in vertebrates remains unknown. We identify SPARK (sperm protein assembly and receptor-binding key), a conserved multi-protein complex that integrates all known sperm fertilization factors, including TMEM81–IZUMO1–SPACA6 and DCST1/2, together with two newly identified components, TMDD1 and FAM187A. SPARK subunits are mutually dependent for stability in mature sperm, and disruption of any single component causes male sterility in zebrafish and mice. Incubating zebrafish sperm with soluble egg receptor Bouncer partially rescues fertilization of Bouncer-deficient eggs in a SPARK-dependent manner, consistent with egg receptor binding priming the complex for fusion. Thus, we propose SPARK as a con-served molecular machine that couples gamete recognition to membrane...
Speaker(s): Germany, Institute of Molecular Pathology in Vienna, Victoria Deneke
Host: Gautam Dey
Place: Small Operon
EMBL Heidelberg, Virtual
Additional information
Abstract
Fertilization requires gamete recognition and membrane fusion, yet the molecular basis of this process in vertebrates remains unknown. We identify SPARK (sperm protein assembly and receptor-binding key), a conserved multi-protein complex that integrates all known sperm fertilization factors, including TMEM81–IZUMO1–SPACA6 and DCST1/2, together with two newly identified components, TMDD1 and FAM187A. SPARK subunits are mutually dependent for stability in mature sperm, and disruption of any single component causes male sterility in zebrafish and mice. Incubating zebrafish sperm with soluble egg receptor Bouncer partially rescues fertilization of Bouncer-deficient eggs in a SPARK-dependent manner, consistent with egg receptor binding priming the complex for fusion. Thus, we propose SPARK as a con-served molecular machine that couples gamete recognition to membrane fusion.
Connection details
Zoom*: [https://www.google.com/url?q=https://embl-org.zoom.us/j/94328842098?pwd%3DfkFpTwL3dGati0RDZxaqjv4waJXcrf.1%26jst%3D2&sa=D&source=calendar&ust=1789544319644714&usg=AOvVaw2NP4zguJ2_780CkO2gzj8e] (Meeting ID: [94328842098], Password: [855080])
Please note that the talk will yes/not be recorded.
*For the FAQ section, as a zoom participant, please use either the chat function (the host will read out your question) or the “raise your hand” function and turn on your microphone.