HCMV miR-US22 down-regulation of EGR-1 regulates CD34+ hematopoietic progenitor cell proliferation and viral reactivation

Mikell, Iliyana; Crawford, Lindsey B.; Hancock, Meaghan H.; Mitchell, Joan S.; Buehler, Jason; Goodrum, Felicia; Nelson, Jay A.

doi:10.1371/journal.ppat.1007854

Cited by 38 publications

(65 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Initial PI3K/AKT activation is required for efficient viral entry as well as optimal replication in fibroblasts and establishment of latency in monocytes [156,158,[160][161][162][163]. However, at later times during infection inhibition of EGFR or PI3K seems to favour viral replication and reactivation from latency suggesting a negative regulatory role at this point [164][165][166][167]. Besides PI3K/AKT signalling, various other kinase pathways are known to be activated very early during HCMV infection.…”

Section: Transcriptional Control Of the Major Ie Genementioning

confidence: 99%

Bright and Early: Inhibiting Human Cytomegalovirus by Targeting Major Immediate-Early Gene Expression or Protein Function

Adamson

Nevels

2020

Viruses

View full text Add to dashboard Cite

The human cytomegalovirus (HCMV), one of eight human herpesviruses, establishes lifelong latent infections in most people worldwide. Primary or reactivated HCMV infections cause severe disease in immunosuppressed patients and congenital defects in children. There is no vaccine for HCMV, and the currently approved antivirals come with major limitations. Most approved HCMV antivirals target late molecular processes in the viral replication cycle including DNA replication and packaging. “Bright and early” events in HCMV infection have not been exploited for systemic prevention or treatment of disease. Initiation of HCMV replication depends on transcription from the viral major immediate-early (IE) gene. Alternative transcripts produced from this gene give rise to the IE1 and IE2 families of viral proteins, which localize to the host cell nucleus. The IE1 and IE2 proteins are believed to control all subsequent early and late events in HCMV replication, including reactivation from latency, in part by antagonizing intrinsic and innate immune responses. Here we provide an update on the regulation of major IE gene expression and the functions of IE1 and IE2 proteins. We will relate this insight to experimental approaches that target IE gene expression or protein function via molecular gene silencing and editing or small chemical inhibitors.

show abstract

Section: Transcriptional Control Of the Major Ie Genementioning

confidence: 99%

Bright and Early: Inhibiting Human Cytomegalovirus by Targeting Major Immediate-Early Gene Expression or Protein Function

Adamson

Nevels

2020

Viruses

View full text Add to dashboard Cite

show abstract

“…Mikell et al have identified a CMV micro RNA transcribed within the US22 open reading frame (miR-US22) that targets EGR1, resulting in a 2 to 5-fold decrease in EGR1 protein levels depending on cell type and is required for reactivation (41). A miR-US22-mutant (ΔUS22) virus results in increased expression of EGR1 and fails to reactivate.…”

Section: Resultsmentioning

confidence: 99%

“…2 and 5C). Additionally, the CMV miroRNA, miR-US22, targets EGR1 messages and is necessary for the reactivation from latency(41). In collaboration with the Nelson group, we show that miR-US22 targeting of EGR1 reduces UL138 expression.…”

Section: Discussionmentioning

confidence: 99%

“…Loss of EGR1 binding in TB40/E-ΔEGR1 Site 1 was confirmed by ChIP-qPCR, described below. TB40/E GFP ΔmiR-US22 was created as described in Mikell et al (41).…”

Section: Methodsmentioning

confidence: 99%

“…Plasmid transfections were carried out in HEK293T/17 cells using PEI at 1 μg of DNA to 3 μg PEI. Plasmid encoding shRNA of EGR1 was described in Mikell et al (41).…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

EGR1 transcriptional control of human cytomegalovirus latency

Buehler

Carpenter

Zeltzer

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

34Sustained phosphotinositide3-kinase (PI3K) signaling is critical to the maintenance of 35 herpesvirus latency. We have previously shown that the beta-herpesvirus, human 36 cytomegalovirus (CMV), regulates epidermal growth factor receptor (EGFR), upstream of PI3K, 37 to control states of latency and reactivation. Inhibition of EGFR signaling enhances CMV 38 reactivation from latency and increases viral replication, but the mechanisms by which EGFR 39 impacts replication and latency is not known. We demonstrate that HCMV downregulates 40 MEK/ERK and AKT phosphorylation, but not STAT3 or PLCγ for productive replication. 41Similarly, inhibition of either MEK/ERK or PI3K/AKT, but not STAT or PLCγ, pathways increases 42 viral reactivation from latently infected CD34 + hematopoietic progenitor cells (HPCs), defining a 43 role for these pathways in latency. We hypothesized that CMV modulation of EGFR signaling 44 might impact viral transcription. Indeed, EGF-stimulation increased expression of the UL138 45 latency gene, but not immediate early or early viral genes, suggesting that EGFR signaling 46 promotes latent gene expression. The early growth response-1 (EGR1) transcription factor is 47 induced downstream of EGFR signaling through both PI3K/AKT and MEK/ERK pathways. 48 EGR1 expression is important for the maintenance of HPC stemness and its downregulation 49 drives HPC differentiation and mobilization. We demonstrate that EGR1 binds upstream of 50 UL138 and is sufficient to promote UL138 expression. Further, disruption of EGR1 binding 51 upstream of UL138 prevented CMV from establishing a latent infection in CD34 + HPCs. Our 52 results indicate a model whereby UL138 modulation of EGFR signaling feeds back to promote 53 UL138 expression and suppression of replication to establish or maintain viral quiescence. 54 55 AUTHOR SUMMARY 56 Buehler et al. 3CMV regulates EGFR signaling to balance states of viral latency and replication. CMV blocks 57 downstream PI3K/AKT and MEK/ERK signaling pathways through down-regulation of EGFR at 58 the plasma membrane. PI3K/AKT and MEK/ERK signaling increases expression of the EGR1 59 transcription factor that is necessary for the maintenance of stem cell stemness. A decrease in 60 EGR1 expression promotes HPC mobilization to the periphery and differentiation, a known 61 stimulus for CMV reactivation. We identified functional EGR1 binding sites upstream of the 62 UL138 gene and EGR-1 binding stimulates UL138 expression. Additionally, down-regulation of 63 EGR1 by CMV miR-US22 decreases UL138 expression emphasizing the importance of this 64 transcription factor in expression of this latency gene. Lastly, we demonstrate that a CMV 65 mutant virus lacking an upstream EGR1 binding site is unable to establish latency in CD34 + 66HPCs. This study defines one mechanism by which EGFR signaling impacts viral gene 67 expression to promote CMV latency. 68 69 RESULTS 129CMV downregulates total and cell surface levels of EGFR. We previously demonstrated that 130 CMV modulates EGFR total and cell s...

show abstract

Human cytomegalovirus microRNAs: strategies for immune evasion and viral latency

Sabbaghian,

Gheitasi,

Fadaee

et al. 2024

Arch Virol

View full text Add to dashboard Cite

HCMV miR-US22 down-regulation of EGR-1 regulates CD34+ hematopoietic progenitor cell proliferation and viral reactivation

Cited by 38 publications

References 61 publications

Bright and Early: Inhibiting Human Cytomegalovirus by Targeting Major Immediate-Early Gene Expression or Protein Function

Bright and Early: Inhibiting Human Cytomegalovirus by Targeting Major Immediate-Early Gene Expression or Protein Function

EGR1 transcriptional control of human cytomegalovirus latency

Human cytomegalovirus microRNAs: strategies for immune evasion and viral latency

Contact Info

Product

Resources

About