PMID- 35862696 OWN - NLM STAT- MEDLINE DCOM- 20220729 LR - 20230112 IS - 1098-5514 (Electronic) IS - 0022-538X (Print) IS - 0022-538X (Linking) VI - 96 IP - 14 DP - 2022 Jul 27 TI - Human Cytomegalovirus Manipulates Syntaxin 6 for Successful Trafficking and Subsequent Infection of Monocytes. PG - e0081922 LID - 10.1128/jvi.00819-22 [doi] LID - e00819-22 AB - Human cytomegalovirus (HCMV) exhibits a complex host-pathogen interaction with peripheral blood monocytes. We have identified a unique, cell-type specific retrograde-like intracellular trafficking pattern that HCMV utilizes to gain access to the monocyte nucleus and for productive infection. We show that infection of primary human monocytes, epithelial cells, and fibroblasts leads to an increase in the amount of the trafficking protein Syntaxin 6 (Stx6). However, only knockdown (KD) of Stx6 in monocytes inhibited viral trafficking to the trans-Golgi network (TGN), a requisite step for nuclear translocation in monocytes. Conversely, KD of Stx6 in epithelial cells and fibroblasts did not change the kinetics of nuclear translocation and productive infection. Stx6 predominantly functions at the level of the TGN where it facilitates retrograde transport, a trafficking pathway used by only a few cellular proteins and seldom by pathogens. We also newly identify that in monocytes, Stx6 exhibits an irregular vesicular localization rather than being concentrated at the TGN as seen in other cell-types. Lastly, we implicate that viral particles that associate with both Stx6 and EEA1 early in infection are the viral population that successfully traffics to the TGN at later time points and undergo nuclear translocation. Additionally, we show for the first time that HCMV enters the TGN, and that lack of Stx6 prevents viral trafficking to this organelle. We argue that we have identified an essential cell-type specific regulator that controls early steps in efficient productive infection of a cell-type required for viral persistence and disease. IMPORTANCE Human cytomegalovirus (HCMV) infection causes severe and often fatal disease in the immunocompromised. It is one of the leading infectious causes of birth defects and causes severe complications in transplant recipients. By uncovering the unique pathways used by the virus to infect key cells, such as monocytes, responsible for dissemination and persistence, we provide new potential targets for therapeutic intervention. FAU - Mosher, Bailey S AU - Mosher BS AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Molecular & Tumor Virology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Applied Immunology and Pathological Processes, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Excellence in Emerging Viral Threats, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. FAU - Fulkerson, Heather L AU - Fulkerson HL AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Molecular & Tumor Virology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. FAU - Boyle, Tori AU - Boyle T AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. FAU - Chesnokova, Liudmila S AU - Chesnokova LS AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Molecular & Tumor Virology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. FAU - Cieply, Stephen J AU - Cieply SJ AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Molecular & Tumor Virology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. FAU - Yurochko, Andrew D AU - Yurochko AD AUID- ORCID: 0000-0002-6452-5813 AD - Department of Microbiology & Immunology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Molecular & Tumor Virology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Applied Immunology and Pathological Processes, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Cardiovascular Diseases and Sciences, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Feist-Weiller Cancer Center, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Excellence in Arthritis and Rheumatology, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. AD - Center for Excellence in Emerging Viral Threats, Louisiana State University Health Shreveport, Shreveport, Louisiana, USA. LA - eng GR - P01 AI127335/AI/NIAID NIH HHS/United States GR - AI127335/HHS | National Institutes of Health (NIH)/ GR - P30 GM110703/GM/NIGMS NIH HHS/United States GR - R01 AI056077/AI/NIAID NIH HHS/United States GR - AI056077/HHS | National Institutes of Health (NIH)/ GR - P30GM110703/HHS | National Institutes of Health (NIH)/ GR - P20GM134974/HHS | National Institutes of Health (NIH)/ GR - P20GM121288/HHS | National Institutes of Health (NIH)/ GR - P20 GM134974/GM/NIGMS NIH HHS/United States GR - P20GM121307/HHS | National Institutes of Health (NIH)/ GR - P20 GM121288/GM/NIGMS NIH HHS/United States GR - P20 GM121307/GM/NIGMS NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20220711 PL - United States TA - J Virol JT - Journal of virology JID - 0113724 RN - 0 (Qa-SNARE Proteins) RN - 0 (STX6 protein, human) SB - IM MH - *Cytomegalovirus/pathogenicity MH - Humans MH - *Monocytes/virology MH - *Qa-SNARE Proteins/genetics/metabolism MH - Signal Transduction MH - trans-Golgi Network/metabolism PMC - PMC9327712 OTO - NOTNLM OT - HCMV OT - Syntaxin 6 OT - early endosomes OT - monocytes OT - signal transduction OT - trans-Golgi network OT - vesicular trafficking OT - viral trafficking COIS- The authors declare no conflict of interest. EDAT- 2022/07/22 06:00 MHDA- 2022/07/30 06:00 PMCR- 2023/01/11 CRDT- 2022/07/21 14:55 PHST- 2022/07/22 06:00 [pubmed] PHST- 2022/07/30 06:00 [medline] PHST- 2022/07/21 14:55 [entrez] PHST- 2023/01/11 00:00 [pmc-release] AID - 00819-22 [pii] AID - jvi.00819-22 [pii] AID - 10.1128/jvi.00819-22 [doi] PST - ppublish SO - J Virol. 2022 Jul 27;96(14):e0081922. doi: 10.1128/jvi.00819-22. Epub 2022 Jul 11.