Photodynamic effects of protoporphyrin on human erythrocytes. Nature of the cross-linking of membrane proteins

Dubbelman, T. M. A. R.; Goeij, A.F.P.M. De; Steveninck, J. Van

doi:10.1016/0005-2736(78)90309-7

Cited by 125 publications

(47 citation statements)

References 33 publications

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“…Various biologic species have long been known to efficiently photosensitize UV protein crosslinking (27,28) and generally have low cytotoxicity. In our studies, flavins, pyridine nucleotides, and the neurotransmitter serotonin all proved useful for creating 3D defined structures of crosslinked proteins under biologically compatible conditions.…”

Section: Resultsmentioning

confidence: 99%

Guiding neuronal development with in situ microfabrication

Kaehr

Allen

Javier

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

135

146

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We report the ability to modify microscopic 3D topographies within dissociated cultures, providing a means to alter the development of neurons as they extend neurites and establish interconnections. In this approach, multiphoton excitation is used to focally excite noncytotoxic photosensitizers that promote protein crosslinking, such as BSA, into matrices having feature sizes >250 nm. Barriers, growth lanes, and pinning structures comprised of crosslinked proteins are fabricated under conditions that do not compromise the viability of neurons both on short time scales and over periods of days. In addition, the ability to fabricate functional microstructures from crosslinked avidin enables submicrometer localization of controllable quantities of biotinylated ligands, such as indicators and biological effectors. Feasibility is demonstrated for using in situ microfabrication to guide the contact position of cortical neurons with micrometer accuracy, opening the possibility for engineering well defined sets of synaptic interactions.biofabrication ͉ multiphoton cell patterning ͉ growth cone S tudies of neuronal function increasingly rely on methods for precisely manipulating cellular properties. Innovations in electrophysiology, photolytic release of effectors, and inducible knockout technologies (1-3) have made it possible to explore cellular phenomena at levels of reduction few anticipated a quarter-century ago. Despite this technological revolution, approaches for influencing neuronal morphology, motility, and interconnectivity remain relatively primitive, a limitation of considerable importance to fundamental and applied neuroscience. An ability to prescribe the exact location at which an extending neurite makes contact with a target cell, or to constrain neuronal migration at a specific time point in development, would be of great value to studies of signal transduction and integration within individual cells and neural networks.Neurite orientation and growth can be modified in real time by various stimuli, including diffusible neurotrophin gradients (4), electric fields (5), and near-IR light (6), but these approaches exert relatively coarse influences over neurite pathfinding and have not been used to accurately guide cellular interactions. Finer delimitation of neurite development can be achieved by using patterned surfaces and topologies microfabricated in silicon and other materials (7-9); such structures, however, must be prepared before cells are introduced for culture when the detailed features of neurite arborization cannot be known.Multiphoton excitation provides an alternative approach for constructing 3D defined microscopic materials that, in principle, could be fabricated within cellular environments. Used extensively in 3D fluorescence imaging, multiphoton excitation also has proved useful for promoting photochemical reactions with high spatial and temporal control (10-13). Application of this strategy to ''direct-write'' material fabrication can be achieved by focusing light from a pulsed femtosec...

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Section: Resultsmentioning

confidence: 99%

Guiding neuronal development with in situ microfabrication

Kaehr

Allen

Javier

et al. 2004

Proc. Natl. Acad. Sci. U.S.A.

135

146

View full text Add to dashboard Cite

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“…Another mechanism of lamin aggregation is direct modification by PPIX. The precise nature of modification by PPIX remains to be defined, including determining whether it involves crosslinking via bityrosines adducts (Campbell et al, 1998), though modification of histidines with or without crosslinking with consequent aggregation are also possible (Dubbelman et al, 1978). In addition, PPIX has been reported to inhibit cytochrome P450 enzymatic activity (Williams et al, 1992), although the exact nature of PPIXcytochrome P450 adduct formation to our knowledge is not known.…”

Section: Mechanisms Involved In Lamin Aggregate Formationmentioning

confidence: 99%

Lamin aggregation is an early sensor of porphyria-induced liver injury

Singla

Griggs

Kwan

et al. 2013

Journal of Cell Science

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SummaryOxidative liver injury during steatohepatitis results in aggregation and transglutaminase-2 (TG2)-mediated crosslinking of the keratin cytoplasmic intermediate filament proteins (IFs) to form Mallory-Denk body (MDB) inclusions. The effect of liver injury on lamin nuclear IFs is unknown, though lamin mutations in several human diseases result in lamin disorganization and nuclear shape changes. We tested the hypothesis that lamins undergo aggregation during oxidative liver injury using two MDB mouse models: (i) mice fed the porphyrinogenic drug 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) and (ii) mice that harbor a mutation in ferrochelatase (fch), which converts protoporphyrin IX to heme. Dramatic aggregation of lamin A/C and B1 was noted in the livers of both models in association with changes in lamin organization and nuclear shape, as determined by immunostaining and electron microscopy. The lamin aggregates sequester other nuclear proteins including transcription factors and ribosomal and nuclear pore components into high molecular weight complexes, as determined by mass-spectrometry and confirmed biochemically. Lamin aggregate formation is rapid and precedes keratin aggregation in fch livers, and is seen in liver explants of patients with alcoholic cirrhosis. Exposure of cultured cells to DDC, protoporphyrin IX or Nmethyl-protoporphyrin, or incubation of purified lamins with protoporphyrin IX, also results in lamin aggregation. In contrast, lamin aggregation is ameliorated by TG2 inhibition. Therefore, lamin aggregation is an early sensor of porphyria-associated liver injury and might serve to buffer oxidative stress. The nuclear shape and lamin defects associated with porphyria phenocopy the changes seen in laminopathies and could result in transcriptional alterations due to sequestration of nuclear proteins.

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“…Such a viscosity increase likely reflects cross linking reactions, mediated by singlet oxygen or secondary reactive radicals, similar to those observed in model and intracellular protein systems. [27][28][29][30] …”

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confidence: 99%