The reggie protein family consists of two proteins, reggie-1 and -2, also called flotillins, which are highly ubiquitous evolutionarily conserved. Both reggies have been shown to be associated with membrane rafts involved in various cellular processes such as T-cell activation, phagocytosis insulin signalling. However, the exact molecular function these proteins remains determined. In addition, mechanism association reggie-1, does not contain any transmembrane domain, is known. this study,...

Neurons are believed to possess plasmalemmal microdomains and proteins analogous the caveolae caveolin of nonneuronal cells. Caveolae invaginations where activated glycosyl-phosphatidylinositol (GPI)-anchored preferentially assemble transmembrane signaling may occur. Molecular cloning rat reggie-1 -2 (80% identical goldfish reggie proteins) shows that reggie-2 is practically mouse flotillin-1. Flotillin-1 epidermal surface antigen (ESA) (flotillin-2) suggested represent possible membrane in...

Using confocal laser scanning and double immunogold electron microscopy, we demonstrate that reggie-1 -2 are colocalized in ≤0.1-μm plasma membrane microdomains of neurons astrocytes. In astrocytes, do not occur caveolae but clearly outside these structures. Microscopy coimmunoprecipitation show associated with fyn kinase the glycosylphosphatidyl inositol-anchored proteins Thy-1 F3 that, when activated by antibody cross-linking, selectively copatch reggie. Jurkat cells, after cross-linking...

Prion proteins (PrPs) are key players in fatal neurodegenerative disorders, yet their physiological functions remain unclear, as PrP knockout mice develop rather normally. We report a strong loss-of-function phenotype zebrafish embryos, characterized by the loss of embryonic cell adhesion and arrested gastrulation. Zebrafish mouse mRNAs can partially rescue this knockdown phenotype, indicating conserved functions. Using zebrafish, mouse, Drosophila cells, we show that PrP: (1) mediates...

ABSTRACT Fish – in contrast to mammals regenerate retinal ganglion cell axons when the optic nerve is severed. Optic injury leads reexpression of proteins, which typically are first expressed newly differentiated cells and axons. Here we identified two new proteins fish cells, reggie-1 reggie-2, with monoclonal antibody M802 molecular cloning techniques. In normal fish, stained few derived from newborn added lifelong margin. After injury, however, labeled all throughout their path into...

Reggie-1 and -2 proteins (flotillin-2 -1 respectively) form their own type of non-caveolar membrane microdomains, which are involved in important cellular processes such as T-cell activation, phagocytosis signalling mediated by the prion protein insulin; this is consistent with notion that reggie microdomains promote assemblies signalling. While it generally known contain large multiprotein assemblies, exact organization remains elusive. Using chemical cross-linking approaches, we have...

Abstract Retinal ganglion cells (RGCs) in rats were retrogradely labeled with the fluorescent tracer Fluorogold (FG) and subjected to GAP‐43 c‐JUN immunocytochemistry identify those RGSs that are capable of regenerating an axon. After optic nerve section (ONS) simultaneous application FG stump (group 1 experiments), immunoreactive RGCs (between 2 21 days after ONS) always represented a subfraction both FG‐labeled (i.e., surviving) exhibiting c‐JUN. 22% normally present rat retinae 25%...

Reticulon (RTN) genes code for a family of proteins relatively recently described in higher vertebrates.The four known mammalian paralogues (RTN1, -2, -3, and -4/Nogo) have homologous carboxyl termini with two characteristic large hydrophobic regions.Except RTN4-A/Nogo-A, thought to be an inhibitor neurite outgrowth, restricting the regenerative capabilities CNS after injury, functions other members are largely unknown.The overall occurrence RTNs different phyla evolution RTN gene hitherto...

Abstract This is a light and electron microscopic study of the retinotectal pathway: intact after regeneration optic nerve. The spatiotemporal pattern axonal outgrowth termination was studied with methods proline autoradiography, horseradish peroxidase (HRP) labeling, fiber degeneration. spatial order fibers in normal regenerated pathways assessed by labeling small groups intraretinally HRP then tracing them to tectum. labeled occupied greater fraction cross section than tract. At brachial...

ABSTRACT The cellular prion protein (PrP c ) resides in lipid rafts, yet the type of raft and physiological function PrP are unclear. We show here that cross‐linking with specific antibodies leads to 1) capping Jurkat human peripheral blood T cells; 2) cocapping intracellular proteins reggie‐1 reggie‐2; 3) signal transduction as seen by MAP kinase phosphorylation an elevation Ca 2+ concentration; 4) recruitment Thy‐1, TCR/CD3, fyn, lck LAT into cap along local tyrosine F‐actin...

Hematopoietic cells have long been defined as round, nonpolar that show uniform distribution of cell surface-associated molecules. However, recent analyses the immunological synapse and importance lipid microdomains in signaling shed new light on aspect lymphocyte polarization during activation processes, but none molecules implicated so far either process or microdomain residency are known to a preferential localization nonactivated cells. Chemical crosslinking fluorescence resonance energy...

The reggies/flotillins are oligomeric scaffolding proteins for membrane microdomains. We show here that reggie‐1/flotillin‐2 microdomains organized along cortical F‐actin in several cell types. Interaction with is mediated by the SPFH domain as shown vivo co‐localization and vitro binding experiments. Reggie‐1/flotillin‐2 form independent of actin, but disruption or stabilization actin cytoskeleton modulate lateral mobility FRAP. Furthermore, reggie/flotillin can efficiently be immobilized...

The reggies/flotillins—proteins upregulated during axon regeneration in retinal ganglion cells (RGCs)—are scaffolding proteins of microdomains and involved neuronal differentiation. Here, we show that reggies regulate zebrafish (ZF) after optic nerve section (ONS) vivo as well axon/neurite extension hippocampal N2a neurons vitro through signal transduction molecules modulating actin dynamics. ZF reggie-1a, -2a, -2b downregulation by reggie-specific morpholino (Mo) antisense oligonucleotides...

The lipid raft proteins reggie-1 and -2 (flotillins) are implicated in membrane protein trafficking but exactly how has been elusive. We find that associate with the Rab11a, SNX4, EHD1-decorated tubulovesicular recycling compartment HeLa cells directly interacts Rab11a SNX4. Short hairpin RNA-mediated down-regulation of (and -2) reduces association tubular structures impairs transferrin-transferrin receptor (TfR) complex to plasma membrane. Overexpression constitutively active rescues TfR...

Abstract Goldfish and rat optic nerves were cut crushed, respectively, the expression of transcription factor proteins c‐JUN, JUN B, D, c‐FOS, FOS KROX‐24, CREB was investigated in retinal ganglion cells (RGCs) by immunocytochemistry. Immunoreactivities (IRs) followed up to 350 days goldfish upto 22 rat. In RGCs untreated rats, all JUN, FOS, KROX absent whereas constitutively expressed. After nerve goldfish, a JUN‐like immunoreactivity (JUN‐IR) appeared small number central retina after 24...

Prions result from the misfolding and selective accumulation of host-encoded prion protein (PrP) in brain. Despite intensive research on mammalian models, basic questions about biological role PrP evolutionary origin disease remain unanswered. Following our previous identification novel fish homologues, here we generated new sequences performed genomic analysis to demonstrate existence two homologous loci bony fish, which display extensive molecular variation are highly expressed adult...