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The cell biology of vision.

Sung CH, Chuang JZ - J. Cell Biol. (2010)

Bottom Line: Humans possess the remarkable ability to perceive color, shape, and motion, and to differentiate between light intensities varied by over nine orders of magnitude.Phototransduction--the process in which absorbed photons are converted into electrical responses--is the first stage of visual processing, and occurs in the outer segment, the light-sensing organelle of the photoreceptor cell.Studies of genes linked to human inherited blindness have been crucial to understanding the biogenesis of the outer segment and membrane-trafficking of photoreceptors.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, NY 10065, USA. chsung@med.cornell.edu

ABSTRACT
Humans possess the remarkable ability to perceive color, shape, and motion, and to differentiate between light intensities varied by over nine orders of magnitude. Phototransduction--the process in which absorbed photons are converted into electrical responses--is the first stage of visual processing, and occurs in the outer segment, the light-sensing organelle of the photoreceptor cell. Studies of genes linked to human inherited blindness have been crucial to understanding the biogenesis of the outer segment and membrane-trafficking of photoreceptors.

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OS morphology during normal rod development and in disease. (A) A drawing depicting the transformation of developing rods during their OS morphogenesis. (B) Representative electron micrograph of postnatal day 10 rat rods. This morphological appearance may represent a stage in OS morphogenesis. Many discs are longer than the matured discs; running in parallel to the ciliary stalk (unpublished data). Bar, 0.5 µm. (C) A rod from a postnatal day 15 mouse lacking RPGRIP1 (RPGRIP1−/−) containing vertically oriented discs is shown. Reproduced from Zhao et al. (2003), copyright The National Academy of Sciences, USA. Bar, 0.2 µm.
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fig3: OS morphology during normal rod development and in disease. (A) A drawing depicting the transformation of developing rods during their OS morphogenesis. (B) Representative electron micrograph of postnatal day 10 rat rods. This morphological appearance may represent a stage in OS morphogenesis. Many discs are longer than the matured discs; running in parallel to the ciliary stalk (unpublished data). Bar, 0.5 µm. (C) A rod from a postnatal day 15 mouse lacking RPGRIP1 (RPGRIP1−/−) containing vertically oriented discs is shown. Reproduced from Zhao et al. (2003), copyright The National Academy of Sciences, USA. Bar, 0.2 µm.

Mentions: Rod differentiation in rodents starts postnatally, and it takes 2–3 wk for the OS to fully mature (LaVail, 1973). OS morphogenesis among the rods is not completely synchronized throughout development until near the end. It begins with the extension of a primitive cilium from the basal body anchored on the plasma membrane (Fig. 3 A). This rudimentary cilium has the morphological appearance of a typical primary cilium. The apical end of a primitive cilium gradually becomes swollen and filled with a variety of membranous vesicles, tubules, and sacs. At postnatal days 8–10, disc-like membranous cisternae begin to fill the developing OS; however, these discs are often excessively long and highly disorganized (Fig. 3 B; De Robertis, 1956, 1960; Besharse et al., 1985). Many of them are aligned parallel to or at an oblique angle relative to the ciliary stalk. The next phase of OS differentiation involves a major remodeling that reorganizes the discs to align perpendicular to the ciliary stalk, making them stackable. The terminal phase of rod differentiation is the elongation of the OS; the lengths of OSs containing orderly disc stacks increase at an almost linear rate during this period until the OSs reach their mature size (LaVail, 1973).


The cell biology of vision.

Sung CH, Chuang JZ - J. Cell Biol. (2010)

OS morphology during normal rod development and in disease. (A) A drawing depicting the transformation of developing rods during their OS morphogenesis. (B) Representative electron micrograph of postnatal day 10 rat rods. This morphological appearance may represent a stage in OS morphogenesis. Many discs are longer than the matured discs; running in parallel to the ciliary stalk (unpublished data). Bar, 0.5 µm. (C) A rod from a postnatal day 15 mouse lacking RPGRIP1 (RPGRIP1−/−) containing vertically oriented discs is shown. Reproduced from Zhao et al. (2003), copyright The National Academy of Sciences, USA. Bar, 0.2 µm.
© Copyright Policy - openaccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3101587&req=5

fig3: OS morphology during normal rod development and in disease. (A) A drawing depicting the transformation of developing rods during their OS morphogenesis. (B) Representative electron micrograph of postnatal day 10 rat rods. This morphological appearance may represent a stage in OS morphogenesis. Many discs are longer than the matured discs; running in parallel to the ciliary stalk (unpublished data). Bar, 0.5 µm. (C) A rod from a postnatal day 15 mouse lacking RPGRIP1 (RPGRIP1−/−) containing vertically oriented discs is shown. Reproduced from Zhao et al. (2003), copyright The National Academy of Sciences, USA. Bar, 0.2 µm.
Mentions: Rod differentiation in rodents starts postnatally, and it takes 2–3 wk for the OS to fully mature (LaVail, 1973). OS morphogenesis among the rods is not completely synchronized throughout development until near the end. It begins with the extension of a primitive cilium from the basal body anchored on the plasma membrane (Fig. 3 A). This rudimentary cilium has the morphological appearance of a typical primary cilium. The apical end of a primitive cilium gradually becomes swollen and filled with a variety of membranous vesicles, tubules, and sacs. At postnatal days 8–10, disc-like membranous cisternae begin to fill the developing OS; however, these discs are often excessively long and highly disorganized (Fig. 3 B; De Robertis, 1956, 1960; Besharse et al., 1985). Many of them are aligned parallel to or at an oblique angle relative to the ciliary stalk. The next phase of OS differentiation involves a major remodeling that reorganizes the discs to align perpendicular to the ciliary stalk, making them stackable. The terminal phase of rod differentiation is the elongation of the OS; the lengths of OSs containing orderly disc stacks increase at an almost linear rate during this period until the OSs reach their mature size (LaVail, 1973).

Bottom Line: Humans possess the remarkable ability to perceive color, shape, and motion, and to differentiate between light intensities varied by over nine orders of magnitude.Phototransduction--the process in which absorbed photons are converted into electrical responses--is the first stage of visual processing, and occurs in the outer segment, the light-sensing organelle of the photoreceptor cell.Studies of genes linked to human inherited blindness have been crucial to understanding the biogenesis of the outer segment and membrane-trafficking of photoreceptors.

View Article: PubMed Central - HTML - PubMed

Affiliation: Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, NY 10065, USA. chsung@med.cornell.edu

ABSTRACT
Humans possess the remarkable ability to perceive color, shape, and motion, and to differentiate between light intensities varied by over nine orders of magnitude. Phototransduction--the process in which absorbed photons are converted into electrical responses--is the first stage of visual processing, and occurs in the outer segment, the light-sensing organelle of the photoreceptor cell. Studies of genes linked to human inherited blindness have been crucial to understanding the biogenesis of the outer segment and membrane-trafficking of photoreceptors.

Show MeSH
Related in: MedlinePlus