Related Experiment Video

Updated: Aug 9, 2026

Using Fluorescent Proteins to Monitor Glycosome Dynamics in the African Trypanosome
10:04

Using Fluorescent Proteins to Monitor Glycosome Dynamics in the African Trypanosome

Published on: August 19, 2014

Frog cones as well as Müller cells have peroxisomes

R St Jules1, J Kennard, W Setlik

  • 1Department of Biological Sciences, Columbia University.

Experimental Eye Research
|January 1, 1992
PubMed

Insights

Researchers identified D-amino acid oxidase in peroxisomes within frog retina Müller cells and cone photoreceptors. This finding reveals previously unknown peroxisome distribution in vertebrate retinas, suggesting roles in lipid metabolism and amino acid oxidation.

Area of Science:

  • Cell Biology
  • Neuroscience
  • Ophthalmology

Background:

  • Peroxisomes are vital organelles involved in various metabolic processes.
  • Previous studies have not extensively characterized peroxisomes in the vertebrate retina.
  • D-amino acid oxidase (DAO) is an enzyme with known functions in amino acid metabolism.

Purpose of the Study:

  • To localize D-amino acid oxidase (DAO) within the frog retina.
  • To investigate the presence and distribution of peroxisomes in retinal cells, particularly photoreceptors.
  • To explore potential functions of retinal peroxisomes.

Main Methods:

  • Utilized cerium-based cytochemistry for enzyme localization.
  • Employed modified fixation techniques with lower glutaraldehyde concentrations.
  • Examined tissue using electron microscopy.

Main Results:

  • D-amino acid oxidase (DAO) was localized to peroxisomes in frog retinal Müller cells.
  • A significant population of peroxisomes was observed in Müller cells, concentrated near the outer and inner limiting membranes and in the outer plexiform layer.
  • Peroxisomes were identified in frog cone photoreceptors for the first time in vertebrate photoreceptors, particularly near the ellipsoid.

Conclusions:

  • The study reveals a previously unrecognized abundance and distribution of peroxisomes in the frog retina.
  • The presence of peroxisomes in cone photoreceptors suggests novel roles in these cells.
  • Potential functions include lipid metabolism (e.g., in oil droplets or outer segments) and oxidation of amino acids and small molecules within the neural retina.

More Related Videos

Quantification of Reactive Oxygen Species Using 2′,7′-Dichlorofluorescein Diacetate Probe and Flow-Cytometry in Müller Glial Cells14:25

Quantification of Reactive Oxygen Species Using 2′,7′-Dichlorofluorescein Diacetate Probe and Flow-Cytometry in Müller Glial Cells

Published on: May 13, 2022

Peroxisome Staining in Mammalian Cells Using Peroxisome-Specific Probes05:57

Peroxisome Staining in Mammalian Cells Using Peroxisome-Specific Probes

Published on: December 19, 2025

Related Concept Videos

The Retina01:32

The Retina

The retina is a layer of nervous tissue at the back of the eye that transduces light into neural signals. This process, called phototransduction, is carried out by rod and cone photoreceptor cells in the back of the retina.
Vesicular Tubular Clusters01:45

Vesicular Tubular Clusters

After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
Peroxisomes01:24

Peroxisomes

Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...
Protein Import into the Peroxisomes01:27

Protein Import into the Peroxisomes

Cells contain membrane-bound organelles called peroxisomes that oxidize organic molecules by transferring hydrogen atoms to oxygen, producing hydrogen peroxide. Peroxisomes enzymatically convert the released hydrogen peroxide into water and oxygen.
Peroxisomal Protein Import:
Peroxisomes lack the genetic machinery required to code for their own proteins. Hence, most peroxisomal membrane, lumenal and transmembrane proteins are synthesized in the cytoplasm or ER and transported to the peroxisome...
Anatomy of the Eyeball01:20

Anatomy of the Eyeball

The eye is a spherical, hollow structure composed of three tissue layers. The outer layer — the fibrous tunic, comprises the sclera — a white structure — and the cornea, which is transparent. The sclera encompasses some of the ocular surface, most of which is not visible. However, the 'white of the eye' is distinctively visible in humans compared to other species. The cornea, a clear covering at the front of the eye, enables light penetration. The eye's middle layer, the vascular tunic,...
Photoreceptors and Visual Pathways01:22

Photoreceptors and Visual Pathways

At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...