Microbial arms race: Ballistic "nematocysts" in dinoflagellates represent a new extreme in organelle complexity.
Sci Adv
; 3(3): e1602552, 2017 Mar.
Article
en En
| MEDLINE
| ID: mdl-28435864
ABSTRACT
We examine the origin of harpoon-like secretory organelles (nematocysts) in dinoflagellate protists. These ballistic organelles have been hypothesized to be homologous to similarly complex structures in animals (cnidarians); but we show, using structural, functional, and phylogenomic data, that nematocysts evolved independently in both lineages. We also recorded the first high-resolution videos of nematocyst discharge in dinoflagellates. Unexpectedly, our data suggest that different types of dinoflagellate nematocysts use two fundamentally different types of ballistic mechanisms one type relies on a single pressurized capsule for propulsion, whereas the other type launches 11 to 15 projectiles from an arrangement similar to a Gatling gun. Despite their radical structural differences, these nematocysts share a single origin within dinoflagellates and both potentially use a contraction-based mechanism to generate ballistic force. The diversity of traits in dinoflagellate nematocysts demonstrates a stepwise route by which simple secretory structures diversified to yield elaborate subcellular weaponry.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Dinoflagelados
/
Orgánulos
Aspecto:
Determinantes_sociais_saude
Límite:
Animals
Idioma:
En
Revista:
Sci Adv
Año:
2017
Tipo del documento:
Article
País de afiliación:
Canadá