ライフサイエンスコーパス: rod outer segment

1 processing for all-trans retinol within the rod outer segment.

2 portional to the square of the length of the rod outer segment.

3 own about their transport and sorting to the rod outer segment.

4 cellular compartment of its functioning, the rod outer segment.

5 odamage than are the major proteins from the rod outer segment.

6 se in the rod inner segment but faint in the rod outer segment.

7 phototransduction) identified so far in the rod outer segment.

8 he phosphoinositide signaling pathway in the rod outer segment.

9 ly increases phosphorylation of serine 71 in rod outer segment.

10 to maintain the highly ordered structure of rod outer segments.

11 d the mutant opsin localized normally to the rod outer segments.

12 in prepared from hypotonically washed bovine rod outer segments.

13 g low-micromolar solutions of rhodopsin from rod outer segments.

14 ht induces redistribution of arrestin to the rod outer segments.

15 and did not prevent rhodopsin trafficking to rod outer segments.

16 RmP), an ATP-binding cassette transporter in rod outer segments.

17 hydrolysis in a preparation of permeablized rod outer segments.

18 natural substrates for transport by ABCR in rod outer segments.

19 n total guanylyl cyclase activity present in rod outer segments.

20 ntified as a GAP for transducin (Galphat) in rod outer segments.

21 ts of cone photoreceptors and to the tips of rod outer segments.

22 ecombinant protein into truncated salamander rod outer segments.

23 oreceptor cell death, and reduced lengths of rod outer segments.

24 These cells were able to phagocytose rod outer segments.

25 have found PLCbeta4-like immunoreactivity in rod outer segments.

26 ulation of cGMP phosphodiesterase in retinal rod outer segments.

27 lated rods or truncated, internally dialyzed rod outer segments.

28 nal pigment epithelial cells challenged with rod outer segments.

29 d to increased structural instability of the rod outer segments.

30 uclear layer, with only approximately 20% in rod outer segments.

31 3 fatty acid, is the major polyunsaturate in rod outer segments.

32 rt of CNG channels to the plasma membrane of rod outer segments.

33 ate, likely due to reduced levels of GRK1 in rod outer segments.

34 uses a significant reduction of recoverin in rod outer segments, accompanied by its redistribution to

35 n of transducin affinity to the membranes of rod outer segments, achieved by keeping the transducin b

36 mice, human RPE cells exposed to abca4(-/-) rod outer segments adaptively increased expression of bo

37 etics of all-trans retinol formation in frog rod outer segments after rhodopsin bleaching are to a go

38 In membranes isolated from bovine rod outer segments, all of these sites are occupied by t

39 ivity of native CNG channels from salamander rod outer segments also increases and decreases after in

40 however, S-opsin trafficked normally to the rod outer segment and produced functional S-pigment upon

41 nal alleles to assemble the structure of the rod outer segment and/or differences between the ultrast

42 that is comparable with that found in native rod outer segments and 20-fold faster than rhodopsin in

43 carried out after direct solubilization from rod outer segments and after extensive treatments to rem

44 In the rod outer segments and brains of these animals, there we

45 DE6C-A and EGFP-PDE6C-B were targeted to the rod outer segments and concentrated at the disc rims.

46 Rpgrip1homozygous mutants do not form rod outer segments and display mislocalization of rhodop

47 Experiments on native channels in rod outer segments and expressed channels in Xenopus ooc

48 dopsin-knockout mice failed to create normal rod outer segments and instead, elaborated membranous pr

49 PI 3-kinase is present in bovine rod outer segments and its activity appears to be greate

50 he previously characterized ROS-GC1 from the rod outer segments and its modulator is S100beta.

51 purified to apparent homogeneity from bovine rod outer segments and reconstituted into liposomes.

52 cytochemistry localized CEP to photoreceptor rod outer segments and retinal pigment epithelium in mou

53 ess only the mutant rhodopsin develop normal rod outer segments and show minimal rod cell loss even a

54 terminal acyl chains, was extracted from the rod outer segments and subjected to SDS-polyacrylamide g

55 Retinal rod outer segments and the cerebellar granular layer pos

56 ssion levels of Rho in the disc membranes of rod outer segments and the propensity of Rho to form hig

57 ion of the parafoveal (10 degrees eccentric) rod outer segments and visual sensitivity is delayed com

58 The receptors accumulated in rod outer segments and were homogeneously glycosylated.

59 The transgenic S-opsin was targeted to rod outer segments, and formed a pigment with peak absor

60 alization, maintains nearly normal-appearing rod outer segments, and prevents photoreceptor death in

61 is the predominant source of GAP activity in rod outer segments, and RGS9 concentration emerges as a

62 ayer, reduced levels of rhodopsin, disrupted rod outer segments, and widespread accumulation of the t

63 6-8-week-old Lrat-/- mice revealed that the rod outer segments are approximately 35% shorter than th

64 determine the phosphorylation state of Pd in rod outer segments are important in controlling the numb

65 egment function remains normal until >75% of rod outer segments are lost.

66 Therefore, we used rod outer segments as the starting material for the puri

67 higher levels in cone outer segments than in rod outer segments, as was found for the components of t

68 The rod outer segment ATP binding cassette (ABC) transporter

69 found that tagged KIF17 localized along the rod outer segment axoneme when expressed in mouse and X.

70 Rod outer segments begin to degenerate relatively late,

71 ved in quenching phototransduction in bovine rod outer segment (bROS) homogenates.

72 nt successfully enhanced P23H traffic to the rod outer segment, but this led to reduced photoreceptor

73 phosphatase 2A, an endogenous phosphatase in rod outer segments, but not by PP1 or PP2B.

74 noids, all-trans-retinal, is released in the rod outer segment by photoactivated rhodopsin after ligh

75 cifically removed from detergent extracts of rod outer segments by immunodepletion, the extracts lost

76 osphorylation of rhodopsin in urea-extracted rod outer segments by recombinant human beta-adrenergic

77 uishable from rhodopsin purified from bovine rod outer segments by the following criteria: (i) UV/Vis

78 ing normal morphology (including full-length rod outer segments) by the end of the 3 week recovery pe

79 tide-gated channel activity and elevated the rod outer segment Ca2+ concentration in darkness, measur

80 using nuclear protein extracts derived from rod outer segment-challenged, control retinal pigment ep

81 Ankyrin-G localized exclusively to rod outer segments, coimmunoprecipitated with the CNG ch

82 of phosducin in regulating signaling in the rod outer segment compartment and suggest distinct funct

83 PDE6 (type 6 phosphodiesterase) from rod outer segments consists of two types of catalytic su

84 Rod outer segments could be identified by the CARS signa

85 Similar to rod outer segment cyclase, Ca(2+) sensitivity of recombi

86 zed left-right asymmetry, hydrocephalus, and rod outer segment defects, suggesting a pleiotropic defe

87 eration in homozygotes with a loss of proper rod outer segment development and improper disc formatio

88 Our data indicate RPGRIP1 is necessary for rod outer segment development through regulating ciliary

89 regulating photoreceptor gene expression and rod outer segment development.

90 ack of the 11-cis-retinal chromophore during rod outer segment development.

91 In postnatal day 16 (P16) mutants, rod outer segment dimensions and rhodopsin content are c

92 ardt disease and the localization of ABCR to rod outer segment disc membranes, these data suggest tha

93 , and on acyl chain packing were examined in rod outer segment disc membranes.

94 for transport of all-trans-retinal from the rod outer segment discs in the retina and is associated

95 Subretinal microglia contained phagocytized rod outer segment discs.

96 is an ABC transporter of unknown function in rod outer segment discs.

97 prepared from either bovine brain or bovine rod outer segment discs.

98 Rod outer-segment discs were not essential and developed

99 es consisting of asolectin or native retinal rod outer segment disk lipids using n-octyl beta-d-gluco

100 etically stable protein constituting >90% of rod outer segment disk membrane protein.

101 Rod outer segment disk membranes are densely packed with

102 een rhodopsin and RK in a ternary complex on rod outer segment disk membranes, thereby blocking RK in

103 the previously described monomer, in retinal rod outer segment disk membranes.

104 e of acyl chain order found in native bovine rod outer segment disk membranes.

105 The C-terminus of the intracellular retinal rod outer segment disk protein peripherin-2 binds to mem

106 cells) or plasma membrane-derived membranes (rod outer segments) exhibited a uniform fluorescence.

107 es initially developed normally, except that rod outer segments failed to form.

108 r levels of all-trans-retinal and retinol in rod outer segments following light exposure.

109 Retinol is then transported out of the rod outer segment for further processing.

110 Rod outer segment formation and distribution of peripher

111 Further, we found that rod outer segments from dopamine-treated retinas contain

112 cultured fetal-derived human RPE cells with rod outer segments from wild-type or abca4(-/-) retinas.

113 structures of a modified primary cilium, the rod outer segment, from wild-type and genetically defect

114 unique properties of RGS9 match those of the rod outer segment GAP and implicate it as a key element

115 ow that recombinant zGCAP4 stimulated bovine rod outer segment GC in a Ca(2+)-dependent manner.

116 inal calcium-binding protein which activates rod outer segment guanylate cyclase (ROS-GC) in a calciu

117 dicated that the cyclase did not represent a rod outer segment guanylate cyclase (ROS-GC), which is i

118 Rod outer segment guanylate cyclase 1 (ROS-GC1) is a mem

119 f the phosphodiesterase (PDE) from mammalian rod outer segments has been characterized to evaluate th

120 product of retGC-1 were monitored in bovine rod outer segment homogenates, GCAPs-free bovine rod out

121 major component that stimulates GC in bovine rod outer segment homogenates.

122 ores when added to metabolically compromised rod outer segments; however, it was only 11-cis-retinal

123 is a G protein-coupled receptor found in the rod outer segments in the retina, which triggers a visua

124 EGFP-PDE6C is correctly targeted to the rod outer segments in transgenic Xenopus, where it displ

125 dimer was found to form natively in bleached rod outer segments in vitro and when rod outer segments

126 Biochemical analysis of rod outer segments indicates the presence of IR and PTP1

127 alized tracers moved along the length of the rod outer segment, indicating communication between the

128 s and showed normal cellular localization to rod outer segments, indicating that neither rhodopsin st

129 Like rhodopsin, rho-GFP localized to rod outer segments, indicating that rho-GFP was recogniz

130 lated in vitro by protein kinase C from frog rod outer segments, indicating that this kinase could di

131 In giant patches from rod outer segments, inhibition by PIP(2) is intermediate

132 The ABCR protein of the rod outer segment is thought to facilitate movement of t

133 e reduction in the transducin content of the rod outer segments is accompanied by a corresponding red

134 thought that the concentration of Ca(2+) in rod outer segments is controlled by a dynamic balance be

135 The delivery of RGS9 to rod outer segments is likely to be mediated by the DEP d

136 % of the phosphodiesterase activity found in rod outer segments is membrane-bound, and is thought to

137 aARK1) holoenzyme while hbetaARK1 binding to rod outer segments is partially affected.

138 Rod outer segments isolated from bovine retina phosphory

139 situ phosphorylation of Pgamma by endogenous rod outer segment kinases was enhanced severalfold upon

140 ults suggest that developmental increases in rod outer segment length and rhodopsin density account f

141 ich are stimulated by extracellular ligands, rod outer segment membrane guanylate cyclase (ROS-GC) ac

142 Rod outer segment membrane guanylate cyclase (ROS-GC) tr

143 This system operates via a Ca(2+)-driven rod outer segment membrane guanylate cyclase (ROS-GC).

144 The rod outer segment membrane guanylate cyclase type 1 (ROS

145 Photoreceptor ROS-GC1 (rod outer segment membrane guanylate cyclase) is a vital

146 Rod outer segment membrane guanylate cyclase1 (ROS-GC1)

147 equires functional retinal degeneration slow/rod outer segment membrane protein 1 (Rds/Rom-1) complex

148 S and the unglycosylated RDS binding partner rod outer segment membrane protein 1 (ROM-1) were found

149 ation along with its binding partner, ROM-1 (rod outer segment membrane protein 1).

150 nes cannot interact with its binding partner rod outer segment membrane protein 1.

151 tly opened cGMP-gated cation channels in the rod outer segment membrane that allow Na(+) and Ca(2+) i

152 activated rhodopsin was measured in purified rod outer segment membranes according to the increase in

153 outer segment homogenates, GCAPs-free bovine rod outer segment membranes and recombinant bovine retGC

154 rans retinal from bleached rhodopsin in frog rod outer segment membranes and the rate of all-trans re

155 Here we demonstrate that rod outer segment membranes contain a limited number of

156 hromophore 11-Z-retinylidene of rhodopsin in rod outer segment membranes from bovine retina.

157 om endogenous or recombinant RGS9-1 bound to rod outer segment membranes left RGS9-1 tightly membrane

158 Binding of the mutant proteins to rod outer segment membranes occurs at lower Ca2+ concent

159 is able to detach PDE partially from bovine rod outer segment membranes under physiological conditio

160 beta1gamma1 The complex was formed on native rod outer segment membranes upon light activation, solub

161 d-free form of rhodopsin, was measured using rod outer segment membranes with densities of opsin and

162 Incubation of rod outer segment membranes with phosphoinositide-specif

163 rhodopsin, contained in urea-treated bovine rod outer segment membranes, and the extent of phosphory

164 lectively released PDE6 (but not GARP2) from rod outer segment membranes, demonstrating the specifici

165 1 phosphorylation by an endogenous kinase in rod outer segment membranes, with an average stoichiomet

166 on comparable with the rates of rhodopsin in rod outer segment membranes.

167 quivalent to its endogenous concentration in rod outer segment membranes.

168 Rhodopsins are densely packed in rod outer-segment membranes to maximize photon absorptio

169 the data show that both mislocalization and rod outer segment morphogenesis are likely associated wi

170 gram activity, and visual acuity, indicating rod outer segment morphogenesis proceeded normally in Ra

171 alyzes reduction of all-trans-retinal in the rod outer segment, most noticeably at higher light inten

172 e light-dispersed transducin subunits to the rod outer segments, occurs six times faster than reporte

173 g on specialized post-Golgi membranes to the rod outer segment of the photoreceptor cell.

174 ulation of trace metal concentrations in the rod outer segment of the retina may be important both ph

175 Rhodopsin purified from rod outer segments of bovine retinae by immunoaffinity c

176 In the rod outer segments of GC double knock-out mice, guanylat

177 ation of post-Golgi carriers targeted to the rod outer segments of retinal photoreceptors.

178 The rod outer segments of RK-/- mice raised in 12-hr cyclic

179 fluorescence changes after bleaching in the rod outer segments of Rpe65(-/-) mice, which lack 11-cis

180 In rod outer segments, only 4-HHE-modified proteins increas

181 gh mammalian cell opsin migrates slower than rod outer segment opsin on SDS/polyacrylamide gels, pres

182 a 200-fold intensity range caused correlated rod outer segment (OS) elongation and increased light sc

183 Rod outer segment (OS) lamination, when detectable, was

184 72W protein and the key RDS-binding partner, rod outer segment (OS) membrane protein 1 (ROM-1), were

185 PRPH2 oligomerizes with its homologue rod outer segment (OS) membrane protein 1 (ROM1), and no

186 ent redistribution of transducin between the rod outer segments (OS) and other photoreceptor compartm

187 Shortening of rod outer segments (OS) was observed at approximately 10

188 In cultured RPE-J cells incubated with rod outer segments (OS), siRNA knockdown of Grb2 had no

189 Rpgrip1(tm1Tili) mice, they do not elaborate rod outer segments (OS).

190 The degeneration of rods' outer segments (OSs) is predominant, followed by t

191 rmal retinal pigment epithelial cells during rod outer segment phagocytosis but not during phagocytos

192 Rod outer segment phagocytosis was measured using a flow

193 tron microscopes and function was assayed by rod outer segment phagocytosis.

194 used to determine whether plasma, liver, and rod outer segment phospholipid composition can be altere

195 fatty acid composition of plasma, liver, and rod outer segment phospholipids were examined.

196 Measurements of the rod outer segment photocurrent in transgenic mice, which

197 as substantial as the desensitization of the rod outer segment photocurrent.

198 g its difference in desensitization with the rod outer segment photocurrent.

199 The rod outer segment phototransduction GAP (GTPase-accelera

200 and the thickness of the ONL and that of the rod outer-segment plus inner-segment layer were measured

201 nct from other Ser/Thr kinases identified in rod outer segment preparations including protein kinase

202 The rate of Pd phosphorylation in rod outer segment preparations was dependent on [cAMP].

203 The synthesis of cAMP by adenylyl cyclase in rod outer segment preparations was found to be dependent

204 ly reported for RDH activity in crude bovine rod outer segment preparations.

205 a specific interaction between IRBP and the rod outer segment, probably mediated by a receptor.

206 ansduction cascade in preparations of broken rod outer segments, probably due to a functional uncoupl

207 540 nm) appears in frog and wild-type mouse rod outer segments reaching a maximum in 30-60 min at ro

208 The R838S RetGC1 expression in rod outer segments reduced inhibition of cGMP production

209 the dim light photocurrent is 3-5 microm in rod outer segments, regardless of their absolute size.

210 inding that targeting of CNG channels to the rod outer segment required their interaction with ankyri

211 Dialysis of rhodopsin isolated from bovine rod outer segments resulted in the formation of a new tw

212 as achieved between results for COS-cell and rod outer segment rhodopsin both in kinetics and in the

213 The rod outer segment (ROS) ABC transporter (ABCR) plays an

214 tion change and on acyl chain packing in the rod outer segment (ROS) disk membrane.

215 istant membrane fraction from homogenates of rod outer segment (ROS) disk membranes purified free of

216 -terminal domain that plays crucial roles in rod outer segment (ROS) disk renewal and structure.

217 cipate in disk morphogenesis and localize to rod outer segment (ROS) disk rims.

218 Experiments were conducted on bovine rod outer segment (ROS) disks and on recombinant membran

219 There is evidence that membranes of rod outer segment (ROS) disks are a high-affinity Ca(2+)

220 sphorylation upon flash activation of Rho in rod outer segment (ROS) homogenates.

221 improved retinal pigmented epithelium (RPE)-rod outer segment (ROS) interface were observed after su

222 t phosphoinositide 3-kinase (PI3K) in bovine rod outer segment (ROS) is activated in vitro by tyrosin

223 ted from whole retinas, the thickness of the rod outer segment (ROS) layer was measured, large phagos

224 Rs1-KO rod outer segment (ROS) length was significantly shorter

225 role of peripherin/rds in the maintenance of rod outer segment (ROS) membrane fusion processes.

226 lcholine (PC) recombinants versus the native rod outer segment (ROS) membranes by means of flash phot

227 nsducin reconstituted with the urea-stripped rod outer segment (ROS) membranes by more than 10-fold t

228 3 FA deficiency on GPCR signaling in retinal rod outer segment (ROS) membranes isolated from rats rai

229 Rho with TM1, TM2, TM4, and TM5 peptides in rod outer segment (ROS) membranes shifted the resulting

230 mprising the macular pigment, are present in rod outer segment (ROS) membranes where the concentratio

231 udy the authors examined IGF-1R signaling in rod outer segment (ROS) membranes.

232 were used to measure melanosome motility and rod outer segment (ROS) phagocytosis and digestion.

233 nal capability of the cells was evaluated by rod outer segment (ROS) phagocytosis.

234 is the predominant esterified fatty acid in rod outer segment (ROS) phospholipids, these findings su

235 sults in tyrosine phosphorylation of several rod outer segment (ROS) proteins.

236 e 3 (slower degeneration) showed progressive rod outer segment (ROS) shortening and outer nuclear lay

237 ners of PrBP/delta in retina and in purified rod outer segment (ROS) suspensions whose physiological

238 nce of the mouse opsin promoter and an opsin rod outer segment (ROS) targeting sequence, localized to

239 Rod outer segment (ROS) uptake, a crucial function of th

240 e specialized light-sensitive organelle, the rod outer segment (ROS).

241 nsible for its polarized distribution to the rod outer segment (ROS).

242 ence of PIPKII alpha in bovine photoreceptor rod outer segments (ROS) and the involvement of tyrosine

243 The morphology of the rod outer segments (ROS) and the thickness of the outer

244 Components I and II (CI&II) in frog rod outer segments (ROS) are prominent cAMP-dependent pr

245 Phagocytosis of shed photoreceptor rod outer segments (ROS) by the retinal pigment epitheli

246 Retinal rod outer segments (ROS) contained approximately 1% each

247 Detergent-resistant membranes isolated from rod outer segments (ROS) have been previously shown to c

248 h whole retinal preparations and in isolated rod outer segments (ROS) in terms of uptake kinetics and

249 called disc membranes that are found in the rod outer segments (ROS) of photoreceptors in the retina

250 lian RetGCs: the content of RetGC1 per mouse rod outer segments (ROS) was at least 3-fold lower, the

251 on purified rod and cone PDE6 and on intact rod outer segments (ROS) were characterized.

252 mily members of the donor suggested that the rod outer segments (ROS) were shortened and that only wi

253 -induced phosphodiesterase (PDE) activity in rod outer segments (ROS) with excess arrestin, increase

254 ater ages there were disorganized, shortened rod outer segments (ROS), and a loss of photoreceptor nu

255 In rod outer segments (ROS), the redox reaction involves al

256 (DHA), the major fatty acid found in retinal rod outer segments (ROS).

257 hometry of the outer nuclear layer (ONL) and rod outer segments (ROS).

258 ount for much of the Galphat GAP activity in rod outer segments (ROS).

259 the accumulation of all-trans-retinal in the rod outer segments (ROS).

260 sure membrane fusion events in photoreceptor rod outer segments (ROS).

261 t and delivery of rhodopsin to photoreceptor rod outer segments (ROS).

262 ation affecting rhodopsin's stabilization of rod outer segments (ROS).

263 s (COS) and the open lamellae at the base of rod outer segments (ROS).

264 cally, CNTF treatment causes a shortening of rod outer segments (ROS).

265 isks of the photoreceptor structures [termed rod outer segments (ROS)], and the lack of other highly

266 Rod outer segments (ROSs) were isolated for Western blot

267 Rhodopsin in the disk membranes of rod outer segments serves as the dim-light photoreceptor

268 st that in retinal pigment epithelial cells, rod outer segment-specific phagocytosis is accompanied b

269 nt rescue of rod function and improvement of rod outer segment structure.

270 phages in the outer retina and photoreceptor rod outer segments (target tissue), but despite showing

271 ce of the mouse opsin promoter and rhodopsin rod outer segment targeting sequence, localized to the p

272 In isolated rod outer segments, the delta subunit was found exclusiv

273 n-sensitive rods; however, in blue-sensitive rod outer segments, there was an enhanced uptake of four

274 resence of a phosphoinositide pathway in the rod outer segment, though its functions and the molecula

275 assumed to regulate light sensitivity in the rod outer segment through interaction with the heterotri

276 gment line was disrupted and blurry, and the rod outer segment tip line was absent.

277 , the G protein transducin translocates from rod outer segments to inner segments/spherules in bright

278 Up to 90% of transducin translocates from rod outer segments to other cellular compartments on the

279 Second, the amount of arrestin entering rod outer segments under these conditions is superstoich

280 ctionally intact isolated Gecko gecko lizard rod outer segments under whole-cell voltage clamp.

281 ation method for PDE6-PrBP/delta from bovine rod outer segments utilizing recombinant PrBP/delta.

282 Soluble phosphodiesterase from these rod outer segments was more highly methylated (4.5 +/- 0

283 elta subunit on the light response of bovine rod outer segments, we measured the real time accumulati

284 The vitamin A-deprived rod outer segments were 60% to 70% the length and diamet

285 Dystrophic rod photoreceptors with truncated rod outer segments were identified as the likely source

286 leached rod outer segments in vitro and when rod outer segments were incubated with ATR.

287 ipulation, and the absorbance spectra of the rod outer segments were measured with a photon-counting

288 The OSL was thinned, rod outer segments were misaligned, and abundant schisis

289 -dependent fluorescent compounds produced in rod outer segments were not transferred to the RPE of mi

290 Bleached (BROS) and dark-adapted (DROS) rod outer segments were prepared from frozen bovine reti

291 Rod outer segments were prepared from the radiolabeled r

292 ly positioned in the mutant retina, although rod outer segments were short and retinal lamination was

293 Pieces of bovine retina with intact rod outer segments were treated with pore-forming staphy

294 is peripherally attached to membranes of the rod outer segment, where it interacts with other protein

295 Incubation of dark-adapted bovine rod outer segments with [gamma-(32)P]ATP led to RGS9-1 p

296 when bound to the delta subunit, we labeled rod outer segments with a tritiated methyl donor.

297 eins from whole retina or partially purified rod outer segments with anti-PLCbeta4 and anti-G(alpha11

298 Retinol also moved along the length of the rod outer segment, with an apparent diffusion coefficien

299 trafficking signal can be transported to the rod outer segment without cotransporting with full-lengt

300 ansduction is thought to be contained within rod outer segments without involvement of extrinsic regu