ArticleCurrent biology : CB2014
Function of the male-gamete-specific fusion protein HAP2 in a seven-sexed ciliate.
Article in Current biology : CB, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers.
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Who cites it
37 citing papers in PubMed.
- The SPARK complex forms the molecular basis of vertebrate fertilization.bioRxiv : the preprint server for biology · 2026Article
- The Role of Membrane-Bound Extracellular Vesicles During Co-Stimulation and Conjugation in the CiliateMicroorganisms · 2025Article
- Structural and antigenic characterization of Babesia Bovis HAP2 domains.Scientific reports · 2025Article
- Novel requirements for HAP2/GCS1-mediated gamete fusion iniScience · 2024Article
- From gametes to zygote: Mechanistic advances and emerging possibilities in plant reproduction.Plant physiology · 2024Review
- Cip1, a CDK regulator, determines heterothallic mating or homothallic selfing in a protist.Proceedings of the National Academy of Sciences of the United States of America · 2024Article
- HOP1 and HAP2 are conserved components of the meiosis-related machinery required for successful mating in Leishmania.Nature communications · 2023Article
- A Frame-by-Frame Glance at Membrane Fusion Mechanisms: From Viral Infections to Fertilization.Biomolecules · 2023Review
- Behavior of Male Gamete Fusogen GCS1/HAP2 and the Regulation inBiomolecules · 2023Article
- DMP8 and 9 regulate HAP2/GCS1 trafficking for the timely acquisition of sperm fusion competence.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- Discovery of archaeal fusexins homologous to eukaryotic HAP2/GCS1 gamete fusion proteins.Nature communications · 2022Article
- Stress conditions promoteeLife · 2022Article
- Using a Hand-Held Gene Gun for Genetic Transformation of Tetrahymena thermophila.Methods in molecular biology (Clifton, N.J.) · 2022Article
- MAR1 links membrane adhesion to membrane merger during cell-cell fusion in Chlamydomonas.Developmental cell · 2021Article
- Species-specific gamete recognition initiates fusion-driving trimer formation by conserved fusogen HAP2.Nature communications · 2021Article
- Sequential production of gametes during meiosis in trypanosomes.Communications biology · 2021Article
- HAP2-Mediated Gamete Fusion: Lessons From the World of Unicellular Eukaryotes.Frontiers in cell and developmental biology · 2021Review
- Fusexins, HAP2/GCS1 and Evolution of Gamete Fusion.Frontiers in cell and developmental biology · 2021Review
- The Transmembrane Protein Semi1 Positions Gamete Nuclei for Reciprocal Fertilization in Tetrahymena.iScience · 2020Article
- The molecular foundations of zygosis.Cellular and molecular life sciences : CMLS · 2020Review
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Abstract
HAP2, a male-gamete-specific protein conserved across vast evolutionary distances, has garnered considerable attention as a potential membrane fusogen required for fertilization in taxa ranging from protozoa and green algae to flowering plants and invertebrate animals [1-6]. However, its presence in Tetrahymena thermophila, a ciliated protozoan with seven sexes or mating types that bypasses the production of male gametes, raises interesting questions regarding the evolutionary origins of gamete-specific functions in sexually dimorphic species. Here we show that HAP2 is expressed in all seven mating types of T. thermophila and that fertility is only blocked when the gene is deleted from both cells of a mating pair. HAP2 deletion strains of complementary mating types can recognize one another and form pairs; however, pair stability is compromised and membrane pore formation at the nuclear exchange junction is blocked. The absence of pore formation is consistent with previous studies suggesting a role for HAP2 in gamete fusion in other systems. We propose a model in which each of the several hundred membrane pores established at the conjugation junction of mating Tetrahymena represents the equivalent of a male/female interface, and that pore formation is driven on both sides of the junction by the presence of HAP2. Such a model supports the idea that many of the disparate functions of sperm and egg were shared by the "isogametes" of early eukaryotes and became partitioned to either male or female sex cells later in evolution.
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