Identification of additional outer segment targeting signals in zebrafish rod opsin
- Fang, X., Peden, A.A., van Eeden, F.J.M., Malicki, J.J.
- Journal of Cell Science 134(6): (Journal)
- Registered Authors
- Malicki, Jarema, van Eeden, Freek
- Cilia, GPCR, Opsin, Photoreceptor, Vision
- MeSH Terms
- Photoreceptor Cells/metabolism
- Photoreceptor Cells, Vertebrate/metabolism
- Protein Transport
- Rod Cell Outer Segment/metabolism
- 33589494 Full text @ J. Cell Sci.
Fang, X., Peden, A.A., van Eeden, F.J.M., Malicki, J.J. (2021) Identification of additional outer segment targeting signals in zebrafish rod opsin. Journal of Cell Science. 134(6):.
In vertebrate photoreceptors, opsins are highly concentrated in a morphologically distinct ciliary compartment known as the outer segment (OS). Opsin is synthesized in the cell body and transported to the OS at a remarkable rate of 100-1000 molecules per second. Opsin transport defects contribute to photoreceptor loss and blindness in human ciliopathies. Previous studies revealed that the opsin C-terminal tail, of 44 amino acids, is sufficient to mediate OS targeting in Xenopus photoreceptors. Here we show that although the Xenopus C-terminus retains this function in zebrafish, the homologous zebrafish sequence is not sufficient to target opsin to the OS. This functional difference is largely caused by a change of a single amino acid present in Xenopus, but not in other vertebrates examined. Furthermore, we find that sequences in the 3rd intracellular cytoplasmic loop (IC3) and adjacent regions of transmembrane helixes 6 and 7 are also necessary for opsin transport in zebrafish. Combined with the cytoplasmic tail, these sequences are sufficient to target opsin to the ciliary compartment.
Genes / Markers
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes