Ultraviolet-A and -B Differentially Modify the Tyrosine-Kinase Profile of Human Keratinocytes and Induce the Expression of Arg†

ABSTRACTThe infectious process of human papillomaviruses (HPVs) has been studied considerably, and many cellular components required for viral entry and trafficking continue to be revealed. In this study, we investigated the role of the nonreceptor tyrosine kinase Pyk2 during HPV16 pseudovirion infection of human keratinocytes. We found that Pyk2 is necessary for infection and appears to be involved in the intracellular trafficking of the virus. Small interfering RNA-mediated reduction of Pyk2 resulted in a significant decrease in infection but did not prevent viral entry at the plasma membrane. Pyk2 depletion resulted in altered endolysosomal trafficking of HPV16 and accelerated unfolding of the viral capsid. Furthermore, we observed retention of the HPV16 pseudogenome in thetrans-Golgi network (TGN) in Pyk2-depleted cells, suggesting that the kinase could be required for the viral DNA to exit the TGN. While Pyk2 has previously been shown to function during the entry of enveloped viruses at the plasma membrane, the kinase has not yet been implicated in the intracellular trafficking of a nonenveloped virus such as HPV. Additionally, these data enrich the current literature on Pyk2's function in human keratinocytes.IMPORTANCEIn this study, we investigated the role of the nonreceptor tyrosine kinase Pyk2 during human papillomavirus (HPV) infection of human skin cells. Infections with high-risk types of HPV such as HPV16 are the leading cause of cervical cancer and a major cause of genital and oropharyngeal cancer. As a nonenveloped virus, HPV enters cells by interacting with cellular receptors and established cellular trafficking routes to ensure that the viral DNA reaches the nucleus for productive infection. This study identified Pyk2 as a cellular component required for the intracellular trafficking of HPV16 during infection. Understanding the infectious pathways of HPVs is critical for developing additional preventive therapies. Furthermore, this study advances our knowledge of intracellular trafficking processes in keratinocytes.

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Formation of 8-hydroxy-2'-deoxyguanosine in the DNA of cultured human keratinocytes by clinically used doses of narrowband and broadband ultraviolet B and psoralen plus ultraviolet A

Cancer Science ◽

10.1111/j.1349-7006.2006.00151.x ◽

2006 ◽

Vol 97 (2) ◽

pp. 99-105 ◽

Cited By ~ 16

Author(s):

Hiroshi Orimo ◽

Yoshiki Tokura ◽

Ryosuke Hino ◽

Hiroshi Kasai

Keyword(s):

Human Keratinocytes ◽

Ultraviolet B ◽

Ultraviolet A

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Ultraviolet A radiation transiently disrupts gap junctional communication in human keratinocytes

AJP Cell Physiology ◽

10.1152/ajpcell.00205.2002 ◽

2003 ◽

Vol 284 (1) ◽

pp. C51-C59 ◽

Cited By ~ 22

Author(s):

Nicolas Provost ◽

Marielle Moreau ◽

Armelle Leturque ◽

Carine Nizard

Keyword(s):

Actin Cytoskeleton ◽

Human Keratinocytes ◽

Ultraviolet A ◽

Gap Junctional Communication ◽

Uva Irradiation ◽

Junctional Communication ◽

Normal Human Keratinocytes ◽

Normal Human ◽

Gap Junctional ◽

Dose Dependent

Ultraviolet A (UVA) (320–400 nm) radiation is known to cause cutaneous aging and skin cancer. We studied the effect of UVA (365 nm) radiation on the human epidermis by focusing on keratinocyte gap junction-mediated intercellular communication (GJIC). We observed a dose-dependent 10-fold decrease in GJIC induced by UVA in normal human keratinocytes. This decrease in GJIC was associated with time-dependent internalization of connexin43 (Cx43). UVA radiation also damaged the actin cytoskeleton, as shown by microfilament disappearance. Importantly, the decrease in GJIC was transient when keratinocytes were irradiated with 10 J/cm2UVA, with a return to baseline values after 8 h. Concomitantly, Cx43 was relocalized and the actin cytoskeleton was restored. UVA irradiation and 12- O-tetradecanoylphorbol 13-acetate (TPA) treatment activated protein kinase C and reduced GJIC. However, Cx43 localization and phosphorylation were differently regulated by the two treatments. This suggests that at least two different pathways may mediate the observed fall in GJIC. These findings identify keratinocyte GJIC as a new UVA target that might sensitize human skin to photoaging and cancer formation.

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Antiapoptotic effects of scutellarin on ultraviolet A-irradiated HaCaT human keratinocytes

Biomedical Dermatology ◽

10.1186/s41702-018-0022-y ◽

2018 ◽

Vol 2 (1) ◽

Author(s):

Mina Choi ◽

Seeun Jeon

Keyword(s):

Human Keratinocytes ◽

Ultraviolet A

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The Activating C-type Lectin-like Receptor NKp65 Signals through a Hemi-immunoreceptor Tyrosine-based Activation Motif (hemITAM) and Spleen Tyrosine Kinase (Syk)

Journal of Biological Chemistry ◽

10.1074/jbc.m116.759977 ◽

2017 ◽

Vol 292 (8) ◽

pp. 3213-3223 ◽

Cited By ~ 1

Author(s):

Björn Bauer ◽

Tanja Wotapek ◽

Tobias Zöller ◽

Emilia Rutkowski ◽

Alexander Steinle

Keyword(s):

Tyrosine Kinase ◽

Cell Activation ◽

Nk Cell ◽

Human Keratinocytes ◽

Sequence Motif ◽

Cellular Cytotoxicity ◽

Spleen Tyrosine Kinase ◽

Cellular Activation ◽

Affinity Interaction ◽

Activation Motif

NKp65 is an activating human C-type lectin-like receptor (CTLR) triggering cellular cytotoxicity and cytokine secretion upon high-affinity interaction with the cognate CTLR keratinocyte-associated C-type lectin (KACL) selectively expressed by human keratinocytes. Previously, we demonstrated that NKp65-mediated cellular cytotoxicity depends on tyrosine 7, located in a cytoplasmic sequence motif of NKp65 resembling a hemi-immunoreceptor tyrosine-based activation motif (hemITAM). HemITAMs have been reported for a few activating myeloid-specific CTLRs, including Dectin-1 and CLEC-2, and consist of a single tyrosine signaling unit preceded by a triacidic motif. Upon receptor engagement, the hemITAM undergoes phosphotyrosinylation and specifically recruits spleen tyrosine kinase (Syk), initiating cellular activation. In this study, we addressed the functionality of the putative hemITAM of NKp65. We show that NKp65 forms homodimers and is phosphorylated at the hemITAM-embedded tyrosine 7 upon engagement by antibodies or KACL homodimers. HemITAM phosphotyrosinylation initiates a signaling pathway involving and depending on Syk, leading to cellular activation and natural killer (NK) cell degranulation. However, although NKp65 utilizes Syk for NK cell activation, a physical association of Syk with the NKp65 hemITAM could not be detected, unlike shown previously for the hemITAM of myeloid CTLR. Failure of NKp65 to recruit Syk is not due to an alteration of the triacidic motif, which rather affects the efficiency of hemITAM phosphotyrosinylation. In summary, NKp65 utilizes a hemITAM-like motif for cellular activation that requires Syk, although Syk appears not to be recruited to NKp65.

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