Photochromic ultrafast reactions of bacteriorhodopsin (H. salinarum) and bovine rhodopsin were conducted with a femtosecond two-pump probe pulse setup with the time resolution of 20-25fs. The dynamics of the forward and reverse photochemical reactions for both retinal-containing proteins was compared. It is demonstrated that when retinal-containing proteins are excited by femtosecond pulses, dynamics pattern of the vibrational coherent wave packets in the course of the reaction is different for bacteriorhodopsin and visual rhodopsin. As shown in these studies, the low-frequencies that form a wave packets experimentally observed in the dynamics of primary products formation as a result of retinal photoisomerization have different intensities and are clearer for bovine rhodopsin. Photo-reversible reactions for both retinal proteins were performed from the stage of the relatively stable photointermediates that appear within 3-5ps after the light pulse impact. It is demonstrated that the efficiency of the reverse phototransition K-form→bacteriorhodopsin is almost five-fold higher than that of the Batho-intermediate→visual rhodopsin phototransition. The results obtained indicate that in the course of evolution the intramolecular mechanism of the chromophore-protein interaction in visual rhodopsin becomes more perfect and specific. The decrease in the probability of the reverse chromophore photoisomerization (all-trans→11-cis retinal) in primary photo-induced rhodopsin products causes an increase in the efficiency of the photoreception process.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jphotobiol.2016.09.041 | DOI Listing |
J Cell Sci
January 2025
Department of Ophthalmology and Visual Sciences, University of New Mexico, Albuquerque, New Mexico 87131, Mexico.
The Rab11-Rabin8-Rab8 ciliogenesis complex regulates the expansion of cilia-derived light-sensing organelles, the rod outer segments, via post-Golgi rhodopsin transport carriers (RTCs). Rabin8, an effector of Rab11 and a nucleotide exchange factor (GEF) for Rab8, is phosphorylated at S272 by NDR2 kinase (aka STK38L), a canine erd gene product linked to the human ciliopathy Leber congenital amaurosis (LCA). Here, we define the step at which NDR2 phosphorylated Rabin8 regulates Rab11-Rab8 succession in X.
View Article and Find Full Text PDFVertebrate vision in dim-light environments is initiated by rod photoreceptor cells that express the photopigment rhodopsin, a G-protein coupled receptor (GPCR). To ensure efficient light capture, rhodopsin is densely packed into hundreds of membrane discs that are tightly stacked within the rod-shaped outer segment compartment. Along with its role in eliciting the visual response, rhodopsin serves as both a building block necessary for proper outer segment formation as well as a trafficking guide for a few outer segment resident membrane proteins.
View Article and Find Full Text PDFSci Rep
December 2024
INCI-UPR3212-CNRS, 8 Allée du Général Rouvillois, 67000, Strasbourg, France.
Mutations in the gene ABCA4 coding for photoreceptor-specific ATP-binding cassette subfamily A member 4, are responsible for Stargardts Disease type 1 (STGD1), the most common form of inherited macular degeneration. STGD1 typically declares early in life and leads to severe visual handicap. Abca4 gene-deletion mouse models of STGD1 accumulate lipofuscin, a hallmark of the disease, but unlike the human disease show no or only moderate structural changes and no functional decline.
View Article and Find Full Text PDFJ Genet Genomics
December 2024
MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China; Key Laboratory of Reproductive Medicine of Guangdong Province, the First Affiliated Hospital and School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China. Electronic address:
Mutations in the Rhodopsin (RHO) gene are the main cause of autosomal dominant retinitis pigmentosa (adRP), 84% of which are pathogenic gain-of-function point mutations. Treatment strategies for adRP typically involve silencing or ablating the pathogenic allele, while normal RHO protein replacement has no meaningful therapeutic benefit. Here, we present an adenine base editor (ABE)-mediated therapeutic approach for adRP caused by RHO point mutations in vivo.
View Article and Find Full Text PDFBiochemistry
December 2024
Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California, Irvine, Irvine, California 92697, United States.
Arrestins halt signal transduction by binding to the phosphorylated C-termini of activated G protein-coupled receptors. Arrestin-1, the first subtype discovered, binds to rhodopsin in rod cells. Mutations in , the gene encoding Arrestin-1, are linked to Oguchi disease, characterized by delayed dark adaptation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!