A novel cellular structure in the retina of insectivorous birds

Tyrrell, Luke P.; Teixeira, Leandro; Dubielzig, Richard R.; Pita, Diana; Baumhardt, Patrice; Moore, Bret A.; Fernández‐Juricic, Esteban

doi:10.1038/s41598-019-51774-w

Cited by 13 publications

(7 citation statements)

References 35 publications

(39 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cones of several species ( 30 – 32 ), including zebrafish ( 33 ), contain large megamitochondria. To examine the distribution of megamitochondria in zebrafish cone clusters, we 3D rendered the three largest mitochondria in manually segmented cones in their respective clusters.…”

Section: Resultsmentioning

confidence: 99%

Daily mitochondrial dynamics in cone photoreceptors

Giarmarco

Brock

Robbings

et al. 2020

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Cone photoreceptors in the retina are exposed to intense daylight and have higher energy demands in darkness. Cones produce energy using a large cluster of mitochondria. Mitochondria are susceptible to oxidative damage, and healthy mitochondrial populations are maintained by regular turnover. Daily cycles of light exposure and energy consumption suggest that mitochondrial turnover is important for cone health. We investigated the three-dimensional (3D) ultrastructure and metabolic function of zebrafish cone mitochondria throughout the day. At night retinas undergo a mitochondrial biogenesis event, corresponding to an increase in the number of smaller, simpler mitochondria and increased metabolic activity in cones. In the daytime, endoplasmic reticula (ER) and autophagosomes associate more with mitochondria, and mitochondrial size distribution across the cluster changes. We also report dense material shared between cone mitochondria that is extruded from the cell at night, sometimes forming extracellular structures. Our findings reveal an elaborate set of daily changes to cone mitochondrial structure and function.

show abstract

Section: Resultsmentioning

confidence: 99%

Daily mitochondrial dynamics in cone photoreceptors

Giarmarco

Brock

Robbings

et al. 2020

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Cones of several species (Knabe et al 1997;Utsumi et al 2020;Tyrrell et al 2019) including zebrafish (Kim et al 2005) contain extremely large megamitochondria. To examine distribution of megamitochondria in cone clusters, we 3-D rendered the three largest mitochondria in each cone from Figure 2D in their respective clusters.…”

Section: Megamitochondria Associate In the Cluster Corementioning

confidence: 99%

Daily mitochondrial dynamics in cone photoreceptors

Giarmarco

Brock

Robbings

et al. 2020

Preprint

View full text Add to dashboard Cite

Cone photoreceptors in the retina are exposed to intense daylight, and have higher energy demands in darkness. Cones produce energy using a large cluster of mitochondria. Mitochondria are susceptible to oxidative damage, and healthy mitochondrial populations are maintained by regular turnover. Daily cycles of light exposure and energy consumption suggest that mitochondrial turnover is important for cone health. We investigated the 3-D ultrastructure and metabolic function of zebrafish cone mitochondria throughout the day. At night cones undergo a mitochondrial biogenesis event, corresponding to an increase in the number of smaller, simpler mitochondria and increased metabolic activity. In the daytime, ER and autophagosomes associate more with mitochondria, and mitochondrial size distribution across the cluster changes. We also report dense material shared between cone mitochondria that is extruded from the cell in darkness, sometimes forming extracellular structures. Our findings reveal an elaborate set of daily changes to cone mitochondrial structure and function.

show abstract

“…The distribution of photoreceptors and oil droplets of cone cells have been described in many avian retinas, and it is known that the distribution of different cone types varies across the retina not only between species, but also between individuals (Budnik et al, 1984; Mariani & Leure‐Dupree, 1978; Meyer & May, 1973; Rahman et al, 2007; Rahman et al, 2007; Tyrrell et al, 2019). These variations reflect differences in sensory capacities and in visual ecology (Coimbra et al, 2015; Hart, 2001a, 2001b, 2004; Hart et al, 2006; Martin, 2017; Mitkus et al, 2014; Rahman et al, 2006, 2007a, 2007b).…”

Section: Introductionmentioning

confidence: 99%

Cone distribution and visual resolution of the yellow‐legged gull, Larus michahellis (Naumann, 1840)

Victory

Segovia

Garcı́a

2021

Anat Histol Embryol

View full text Add to dashboard Cite

The morphological characteristics of the yellow‐legged gull's photoreceptors and cone distribution were studied using light and electron microscopy. In wholemount fresh retinas, five different coloured oil droplets located in the cone inner segments could be seen and characterized by colour, diameter and stratification. The photoreceptors were classified by comparing the fresh and fixed vertical sections under a light and electron microscope. Rods were easily distinguished from cones based on the outer segment morphology and the absence of oil droplets in their inner segments. Four types of single cones were associated with red, yellow, colourless and transparent oil droplets. Unequal double cones comprised a long principal member with a green oil droplet and an accessory short member containing a green microdroplet which was highly electron‐dense under electron microscopy. The different types of oil droplets were counted from microphotographs of fresh retinal samples in 20 regions. The density, percentage and diameter of the oil droplets were determined. The results showed that central regions had the highest oil droplet density which decreased towards the retinal periphery in all quadrants. Moreover, the oil droplet density was higher in the dorsotemporal quadrant than in other retinal regions. The average density of the red oil droplets was highest in the central areas, whereas colourless oil droplets had the highest density throughout the retina. In contrast, transparent oil droplets had the lowest density across all the regions of the retina. Finally, the retinal resolution was 52.61 cycles/degree. It was calculated using the posterior nodal distance and the oil droplet diameter. The work concludes by discussing the significance of the relative proportion of different cone types across the retina.

show abstract

A novel cellular structure in the retina of insectivorous birds

Cited by 13 publications

References 35 publications

Daily mitochondrial dynamics in cone photoreceptors

Daily mitochondrial dynamics in cone photoreceptors

Daily mitochondrial dynamics in cone photoreceptors

Cone distribution and visual resolution of the yellow‐legged gull, Larus michahellis (Naumann, 1840)

Contact Info

Product

Resources

About