A procedure is described to purify and stabilize cattle rod outer segments with an intact plasma membrane. Three criteria are applied to assess the integrity of the latter. Upon photolysis in these rod outer segments: (1) exogenous ATP cannot phosphorylate rhodopsin located in the disk membrane. (2) Endogenous cofactors (NADPH, NADPH-regenerating system) are still available in the rod cytosol and consequently retinol is the final photoproduct of photolysis of rhodopsin. (3) The rod cytosol can maintain a pH different from that of the medium, since the later stages of rhodopsin photolysis are independent of the medium pH. The stability and homogeneity of the preparation appear to be much better than those of freshly isolated frog rod outer segments, which have been used most frequently so far for experiments on the physiology of rod outer segments. In addition, these cattle rod outer segments remain intact during various manipulations and therefore considerably extend the experimental possibilities when intact rod outer segments are required.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0005-2736(79)90182-2 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Revealing the Solution Conformation and Hydration Structure of Type I Tropocollagen Using X-ray Scattering and Molecular Dynamics Simulation.
Biomacromolecules
January 2025
National Synchrotron Radiation Research Center, Hsinchu 300092, Taiwan.
Hydration plays a crucial role in regulating the dispersion behavior of biomolecules in water, particularly in how pH-sensitive hydration water network forms around proteins. This study explores the conformation and hydration structure of Type-I tropocollagen using small- and wide-angle X-ray scattering (SWAXS) and molecular dynamics (MD) simulations. The results reveal that tropocollagen exhibits a significant softening conformation in solution, transitioning from its rod-like structure in tissues to a worm-like conformation, characterized by a reduced radius of gyration of 50 nm and a persistent length of 34 nm.
View Article and Find Full Text PDF"Energetics of the outer retina I: Estimates of nutrient exchange and ATP generation".
PLoS One
December 2024
UCL Institute of Ophthalmology, London, United Kingdom.
Photoreceptors (PRs) are metabolically demanding and packed at high density, which presents a challenge for nutrient exchange between the associated vascular beds and the tissue. Motivated by the ambition to understand the constraints under which PRs function, in this study we have drawn together diverse physiological and anatomical data in order to generate estimates of the rates of ATP production per mm2 of retinal surface area. With the predictions of metabolic demand in the companion paper, we seek to develop an integrated energy budget for the outer retina.
View Article and Find Full Text PDFMettl3-Mediated m6A Modification is Essential for Visual Function and Retinal Photoreceptor Survival.
Invest Ophthalmol Vis Sci
December 2024
The Sichuan Provincial Key Laboratory for Human Disease Gene Study and Center for Medical Genetics, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
Purpose: N6-methyladenosine (m6A) modification, one of the most common epigenetic modifications in eukaryotic mRNA, has been shown to play a role in the development and function of the mammalian nervous system by regulating the biological fate of mRNA. METTL3, the catalytically active component of the m6A methyltransferase complex, has been shown to be essential in development of in the retina. However, its role in the mature retina remains elusive.
View Article and Find Full Text PDFReliability of ameloglyphics in forensic identification: a systematic review.
Int J Legal Med
December 2024
Department of Oral and Maxillofacial Pathology and Microbiology, KLE Vishwanath Katti Institute of Dental Sciences, KLE Academy of Higher Education and Research, Belagavi, 590010, Karnataka, India.
Background: Teeth are considered as hard tissue analogue to fingerprints, being unique to an individual. The enamel which forms the outer layer of the tooth is formed through a highly dynamic process in which ameloblasts lay down enamel rods in an undulating and intertwining path, which is reflected as a series of enamel rod pattern. The study of these patterns is termed as "Ameloglyphics".
View Article and Find Full Text PDFADAM10 Expression by Ameloblasts Is Essential for Proper Enamel Formation.
Int J Mol Sci
December 2024
Division of Biosciences, College of Dentistry, Ohio State University, 305 W, 12th Ave., Columbus, OH 43210, USA.
ADAM10 is a multi-functional proteinase that can cleave approximately 100 different substrates. Previously, it was demonstrated that ADAM10 is expressed by ameloblasts, which are required for enamel formation. The goal of this study was to determine if ADAM10 is necessary for enamel development.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!