Dependence of calmodulin localization in the retina on the NINAC unconventional myosin.

@article{Porter1993DependenceOC,
  title={Dependence of calmodulin localization in the retina on the NINAC unconventional myosin.},
  author={Jeffery A. Porter and M M Yu and Stephen. Doberstein and T D Pollard and Craig Montell},
  journal={Science},
  year={1993},
  volume={262 5136},
  pages={
          1038-42
        }
}
Calmodulin is a highly conserved regulatory protein found in all eukaryotic organisms which mediates a variety of calcium ion-dependent signalling pathways. In the Drosophila retina, calmodulin was concentrated in the photoreceptor cell microvillar structure, the rhabdomere, and was found in lower amounts in the sub-rhabdomeral cytoplasm. This calmodulin localization was dependent on the NINAC (neither inactivation nor afterpotential C) unconventional myosins. Mutant flies lacking the… 

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References

SHOWING 1-10 OF 68 REFERENCES

Differential localizations of and requirements for the two Drosophila ninaC kinase/myosins in photoreceptor cells

It is demonstrated that the ninaC mutation results in light- and age-dependent retinal degeneration, and it is shown that nINAC flies display an electrophysiological phenotype before any discernible retina degeneration indicating that the electrophYSiological defect is the primary effect of the mutation.

Association of calmodulin and an unconventional myosin with the contractile vacuole complex of Dictyostelium discoideum

Results suggest that a calmodulin-binding unconventional myosin is associated with contractile vacuoles in Dictyostelium; similar proteins in yeast and mammalian cells have been implicated in vesicle movement.

Gene encoding cytoskeletal proteins in Drosophila rhabdomeres.

Ulastructural studies show that the polypeptides encoded by ninaC are very likely to be important components of the cytoskeletal structure of rhabdomeral microvilli.

Calmodulin and calmodulin binding proteins in amphibian rod outer segments.

The calmodulin (CaM) content of fully intact frog rod outer segments (ROS) has been measured. The molar ratio between rhodopsin and total CaM in ROS is 800:1. This is in good agreement with the data

Distinct roles of the Drosophila ninaC kinase and myosin domains revealed by systematic mutagenesis

The results indicated that the ERG and retinal degeneration phenotypes were not strictly coupled suggesting that the myosin domain has multiple functions, and it is proposed that the role of the kinase domain is to regulate other rhabdomeric proteins important in phototransduction.

Calmodulin concentrates at regions of cell growth in Saccharomyces cerevisiae

Calmodulin was localized in Saccharomyces cerevisiae by indirect immunofluorescence using affinity-purified polyclonal antibodies and indicates that calmodulin and actin concentrate in overlapping regions during the cell cycle.

Identification of actin filaments in the rhabdomeral microvilli of Drosophila photoreceptors

The present study shows that actin filaments are a component of this cytoskeleton in Drosophila, and provides an indication as to how any myosin that is associated with the rhabdomeres might function.
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