scholarly journals Intra-axonal Translation of SMAD1/5/8 Mediates Retrograde Regulation of Trigeminal Ganglia Subtype Specification

Neuron ◽  
2012 ◽  
Vol 74 (1) ◽  
pp. 95-107 ◽  
Author(s):  
Sheng-Jian Ji ◽  
Samie R. Jaffrey
2001 ◽  
Vol 75 (11) ◽  
pp. 5069-5075 ◽  
Author(s):  
Bretton C. Summers ◽  
Todd P. Margolis ◽  
David A. Leib

ABSTRACT In humans and animal models of herpes simplex virus infection, zosteriform skin lesions have been described which result from anterograde spread of the virus following invasion of the nervous system. Such routes of viral spread have not been fully examined following corneal infection, and the possible pathologic consequences of such spread are unknown. To investigate this, recombinant viruses expressing reporter genes were generated to quantify and correlate gene expression with replication in eyes, trigeminal ganglia, and periocular tissue. Reporter activity peaked in eyes 24 h postinfection and rapidly fell to background levels by 48 h despite the continued presence of viral titers. Reporter activity rose in the trigeminal ganglia at 60 h and peaked at 72 h, concomitant with the appearance and persistence of infectious virus. Virus was present in the periocular skin from 24 h despite the lack of significant reporter activity until 84 h postinfection. This detection of reporter activity was followed by the onset of periocular disease on day 4. Corneal infection with a thymidine kinase-deleted reporter virus displayed a similar profile of reporter activity and viral titer in the eyes, but little or no detectable activity was observed in trigeminal ganglia or periocular tissue. In addition, no periocular disease symptoms were observed. These findings demonstrate that viral infection of periocular tissue and subsequent disease development occurs by zosteriform spread from the cornea to the periocular tissue via the trigeminal ganglion rather than by direct spread from cornea to the periocular skin. Furthermore, clinical evidence is discussed suggesting that a similar mode of spreading and disease occurs in humans following primary ocular infection.


1989 ◽  
Vol 14 (2) ◽  
pp. 95-106 ◽  
Author(s):  
Zofia Wroblewska ◽  
Kathleen Savage ◽  
Jordan G. Spivack ◽  
Nigel W. Fraser

2001 ◽  
Vol 1 ◽  
pp. 5-5 ◽  
Author(s):  
A. F. Russo ◽  
P. L. Durham

The neuropeptide calcitonin gene-related peptide (CGRP) is a potent regulator of cerebral vascular tone and contributes to neurogenic inflammation. Clinical studies have shown that CGRP levels are elevated during the painful phase of migraine headache, then restored to baseline by antimigraine 5-HT1 drugs. Conversely, CGRP is depleted in perivascular nerve terminals from patients who have suffered vasospasm following subarachnoid hemorrhage. We have investigated the mechanisms controlling CGRP expression in the trigeminal ganglia neurons, which provide virtually all of the CGRP innervation to the cerebral vasculature. We found that nerve depolarization, inflammatory compounds, and nitric oxide can increase CGRP synthesis and secretion. Using both adenoviral vectors and transfection approaches, we have shown that the increased synthesis is due to activation of a cell-specific MAP kinase-responsive enhancer upstream of the CGRP gene. Interestingly, the 5-HT1 migraine drugs are able to block this up-regulation by a mechanism that involves a very prolonged elevation of calcium. We have shown that the duration of the calcium signal is a key determinant for whether a MAP kinase responsive gene will be stimulated or repressed by calcium-activated pathways. This observation supports the importance of a finely tuned balance of calcium in the trigeminal neuron, which is intriguing in light of genetic evidence for calcium channel mutations in a rare form of inherited migraine. These studies suggest that modulation of MAP kinase control of the cell-specific CGRP gene enhancer may be a useful therapeutic strategy for neurovascular disorders.


PLoS ONE ◽  
2016 ◽  
Vol 11 (5) ◽  
pp. e0155039 ◽  
Author(s):  
Sara Hougaard Pedersen ◽  
Lasse Maretty ◽  
Roshni Ramachandran ◽  
Jonas Andreas Sibbesen ◽  
Victor Yakimov ◽  
...  

2000 ◽  
Vol 74 (2) ◽  
pp. 934-943 ◽  
Author(s):  
Rui Lu ◽  
Vikram Misra

ABSTRACT The cascade of herpes simplex virus (HSV) gene expression that results in viral replication begins with the activation of viral immediate-early (IE) genes by the virion-associated protein VP16. VP16 on its own is inefficient at associating with complexes formed on IE gene promoters and depends upon the cellular factor HCF for its activity. In this respect VP16 mimics the host basic leucine zipper (bZIP) protein Luman, which also requires HCF for activating transcription. Our objective is to explore interactions between Luman and HCF and to determine if they play a role in the biology of herpesviruses. In this report we show that in cultured cells ectopically expressed Luman was retained in the cytoplasm, where it colocalized with Calnexin, a protein normally associated with the endoplasmic reticulum (ER). Retention of Luman in the ER depends on a hydrophobic segment of the protein that probably serves as a transmembrane domain. Deletion of this domain changed the intracellular location of Luman so that most of the mutant protein was in the nucleus of cells. While HCF was present in the nucleus of most cells, in cells expressing Luman it was retained in the cytoplasm where the two proteins colocalized. This cytoplasmic association of Luman and HCF could also be demonstrated in neurons in trigeminal ganglia removed from cattle soon after death. Cells in tissue culture that expressed Luman, but not a mutant form of the protein that fails to bind HCF, were resistant to a productive infection with HSV type 1 (HSV-1). We hypothesize that similar Luman-HCF interactions in sensory neurons in trigeminal ganglia result in the suppression of viral replication and the establishment of latency. Interestingly, Luman could activate the promoters of IE110 and LAT, two genes that are critical for reactivation of HSV-1 from latency. This suggests a role for Luman in the reactivation process as well.


Sign in / Sign up

Export Citation Format

Share Document