Zoeken
Zoeken kan via de modus 'eenvoudig zoeken' (één veld) of uitgebreid via 'geavanceerd zoeken' (meerdere velden). Zo kan je bv. zoeken op een combinatie van een auteursnaam (auteur), een jaartal (jaar) en een documenttype.
Boekenmand
Nuttige resultaten kan je aanvinken en toevoegen aan een mandje. De inhoud hiervan kan je exporteren of afdrukken (naar bv. PDF).
RSS
Op de hoogte blijven van nieuw toegevoegde publicaties binnen uw interessegebied? Dit kan door een RSS-feed (?) te maken van jouw zoekopdracht.
nieuwe zoekopdracht
Remnants of ancestral larval eyes in an eyeless mollusk? Molecular characterization of photoreceptors in the scaphopod Antalis entalis
Wollesen, T.; McDougall, C.; Arendt, D. (2019). Remnants of ancestral larval eyes in an eyeless mollusk? Molecular characterization of photoreceptors in the scaphopod Antalis entalis. EvoDevo 10: 25. https://dx.doi.org/10.1186/s13227-019-0140-7
In: EvoDevo. BioMed Central: London. ISSN 2041-9139; e-ISSN 2041-9139
|   |
| Trefwoorden |
ASSEMBLEPlus Transnational Access
Scientific Publication
Gastropoda [WoRMS]; Mollusca [WoRMS]; Platynereis Kinberg, 1865 [WoRMS]; Polyplacophora [WoRMS]
Marien/Kust |
| Author keywords |
Apical organ, Evolution and development, Gastropod, Lophotrochozoan, Mollusc, Retinal-binding domain, Spiralia, Vision |
| Auteurs | | Top |
- Wollesen, T.
- McDougall, C.
- Arendt, D.
|
|
|
| Abstract |
Background: Eyes have evolved and been lost multiple times during animal evolution, however, the process of eye loss has only been reconstructed in a few cases. Mollusks exhibit eyes as varied as the octopod camera eye or the gastropod cup eye and are ideal systems for studying the evolution of eyes, photoreceptors, and opsins. Results: Here, we identify genes related to photoreceptor formation and function in an eyeless conchiferan mollusk, the scaphopod Antalis entalis, and investigate their spatial and temporal expression patterns during development. Our study reveals that the scaphopod early mid-stage trochophore larva has putative photoreceptors in a similar location and with a similar gene expression profile as the trochophore of polyplacophoran mollusks. The apical and post-trochal putative photoreceptors appear to co-express go-opsin, six1/2, myoV, and eya, while expression domains in the posterior foot and pavilion (posterior mantle opening) show co-expression of several other candidate genes but not go-opsin. Sequence analysis reveals that the scaphopod Go-opsin amino acid sequence lacks the functionally important lysine (K296; Schiff base) in the retinal-binding domain, but has not accumulated nonsense mutations and still exhibits the canonical G-protein activation domain. Conclusions: The scaphopod Go-opsin sequence reported here is the only known example of a bilaterian opsin that lacks lysine K296 in the retinal-binding domain. Although this may render the Go-opsin unable to detect light, the protein may still perform sensory functions. The location, innervation, development, and gene expression profiles of the scaphopod and polyplacophoran apical and post-trochal photoreceptors suggest that they are homologous, even though the scaphopod post-trochal photoreceptors have degenerated. This indicates that post-trochal eyes are not a polyplacophoran apomorphy but likely a molluscan synapomorphy lost in other mollusks. Scaphopod eye degeneration is probably a result of the transition to an infaunal life history and is reflected in the likely functional degeneration of Go-opsin, the loss of photoreceptor shielding pigments, and the scarce expression of genes involved in phototransduction and eye development. Our results emphasize the importance of studying a phylogenetically broad range of taxa to infer the mechanisms and direction of body plan evolution. |
IMIS is ontwikkeld en wordt gehost door het VLIZ.
