TY - JOUR
T1 - Noninvasive two-photon imaging reveals retinyl ester storage structures in the eye
AU - Imanishi, Yoshikazu
AU - Batten, Matthew L.
AU - Piston, David W.
AU - Baehr, Wolfgang
AU - Palczewski, Krzysztof
PY - 2004/2/2
Y1 - 2004/2/2
N2 - Visual sensation in vertebrates is triggered when light strikes retinal photoreceptor cells causing photoisomerization of the rhodopsin chromophore 11-cis-retinal to all-trans-retinal. The regeneration of pre-illumination conditions of the photoreceptor cells requires formation of 11-cis-retinal in the adjacent retinal pigment epithelium (RPE). Using the intrinsic fluorescence of alltrans-retinyl esters, noninvasive two-photon microscopy revealed previously uncharacterized structures (6.9 ± 1.1 μm in length and 0.8 ± 0.2 μm in diameter) distinct from other cellular organelles, termed the retinyl ester storage particles (RESTs), or retinosomes. These structures form autonomous all-trans-retinyl ester-rich intracellular compartments distinct from other organelles and colocalize with adipose differentiation-related protein. As demonstrated by in vivo experiments using wild-type mice, the RESTs participate in 11-cis-retinal formation. RESTs accumulate in Rpe65-/- mice incapable of carrying out the enzymatic isomerization, and correspondingly, are absent in the eyes of Lrat -/- mice deficient in retinyl ester synthesis. These results indicate that RESTs located close to the RPE plasma membrane are essential components in 11-cis-retinal production.
AB - Visual sensation in vertebrates is triggered when light strikes retinal photoreceptor cells causing photoisomerization of the rhodopsin chromophore 11-cis-retinal to all-trans-retinal. The regeneration of pre-illumination conditions of the photoreceptor cells requires formation of 11-cis-retinal in the adjacent retinal pigment epithelium (RPE). Using the intrinsic fluorescence of alltrans-retinyl esters, noninvasive two-photon microscopy revealed previously uncharacterized structures (6.9 ± 1.1 μm in length and 0.8 ± 0.2 μm in diameter) distinct from other cellular organelles, termed the retinyl ester storage particles (RESTs), or retinosomes. These structures form autonomous all-trans-retinyl ester-rich intracellular compartments distinct from other organelles and colocalize with adipose differentiation-related protein. As demonstrated by in vivo experiments using wild-type mice, the RESTs participate in 11-cis-retinal formation. RESTs accumulate in Rpe65-/- mice incapable of carrying out the enzymatic isomerization, and correspondingly, are absent in the eyes of Lrat -/- mice deficient in retinyl ester synthesis. These results indicate that RESTs located close to the RPE plasma membrane are essential components in 11-cis-retinal production.
KW - Photoreceptor cells
KW - Retinal pigment epithelial cells
KW - Retinoid cycle
KW - Rhodopsin
KW - Two-photon microscopy
UR - http://www.scopus.com/inward/record.url?scp=0842266594&partnerID=8YFLogxK
U2 - 10.1083/jcb.200311079
DO - 10.1083/jcb.200311079
M3 - Article
C2 - 14745001
AN - SCOPUS:0842266594
SN - 0021-9525
VL - 164
SP - 373
EP - 383
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 3
ER -