Isoform-specific C-terminal phosphorylation drives autoinhibition of Casein kinase 1.

Casein kinase 1δ (CK1δ) controls essential biological processes including circadian rhythms and wingless-related integration site (Wnt) signaling, but how its activity is regulated is not well understood. CK1δ is inhibited by autophosphorylation of its intrinsically disordered C-terminal tail. Two CK1 splice variants, δ1 and δ2, are known to have very different effects on circadian rhythms. These variants differ only in the last 16 residues of the tail, referred to as the extreme C termini (XCT), but with marked changes in potential phosphorylation sites. Here, we test whether the XCT of these variants have different effects in autoinhibition of the kinase. Using NMR and hydrogen/deuterium exchange mass spectrometry, we show that the δ1 XCT is preferentially phosphorylated by the kinase and the δ1 tail makes more extensive interactions across the kinase domain. Mutation of δ1-specific XCT phosphorylation sites increases kinase activity both in vitro and in cells and leads to changes in the circadian period, similar to what is reported in vivo. Mechanistically, loss of the phosphorylation sites in XCT disrupts tail interaction with the kinase domain. δ1 autoinhibition relies on conserved anion-binding sites around the CK1 active site, demonstrating a common mode of product inhibition of CK1δ. These findings demonstrate how a phosphorylation cycle controls the activity of this essential kinase.

Biochemical mechanisms of period control within the mammalian circadian clock.

Genetically encoded biological clocks are found broadly throughout life on Earth, where they generate circadian (about a day) rhythms that synchronize physiology and behavior with the daily light/dark cycle. Although the genetic networks that give rise to circadian timing are now fairly well established, our understanding of how the proteins that constitute the molecular 'cogs' of this biological clock regulate the intrinsic timing, or period, of circadian rhythms has lagged behind. New studies probing the biochemical and structural basis of clock protein function are beginning to reveal how assemblies of dedicated clock proteins form and evolve through post-translational regulation to generate circadian rhythms. This review will highlight some recent advances providing important insight into the molecular mechanisms of period control in mammalian clocks with an emphasis on structural analyses related to CK1-dependent control of PER stability.

The Tenacious Treponema: A Retrospective Examination of Syphilis Treatment Disparities in Washington, DC.

BACKGROUND: Since 2000, there have been rising rates of syphilis infections nationally with higher incidence among minorities and persons living with human immunodeficiency virus (HIV) (PLWH). The purpose of this study was to determine syphilis treatment adequacy and factors associated with treatment delay. METHODS: This was a retrospective academic-public health collaboration with the District of Columbia Department of Public Health reviewing surveillance data of all primary, secondary, and early latent syphilis cases diagnosed between January 1, 2015, and December 31, 2019. Data were analyzed using multivariable logistic regression to identify factors associated with delayed treatment >14 days from diagnosis. RESULTS: Among 1852 individuals diagnosed with early syphilis, 93% (1730/1852) were male; 48% (893/1852) were coinfected with HIV; 43% (n = 796/1852) were African American/Black, 27% (n = 492/1852) were White, and race/ethnicity was unknown for 17% (n = 318/1852) of cases. Among 679 PLWH for whom viral load (VL) was known, 41% (278/679) had a VL < 20 copies/mL, and 18% (123/679) had VL >10,000 copies/mL. Treatment adequacy overall was 96.5%. Median time to syphilis treatment was 6 days (interquartile range = 4-7). Factors associated with delay of treatment included refused/unknown race (adjusted odds ratio [aOR], 1.95; 95% confidence interval [CI], 1.00-3.79), and HIV VL > 10,000 copies/mL (aOR, 1.97; 95% CI, 1.08-3.58). CONCLUSIONS: The factors we identified associated with delayed treatment may reflect systemic factors contributing to the increased rates of infection among key populations. This highlights the importance of targeted public health efforts with the goal of reducing transmission of both HIV and syphilis.

Predictors of PrEP Retention and Attrition in an Urban Publicly Funded Safety-net Specialty Clinic.

Pre-exposure prophylaxis (PrEP) is an effective tool for human immunodeficiency virus (HIV) prevention. The purpose of this study is to identify correlates of PrEP retention using patient data from an urban, publicly funded safety-net clinic in Washington, DC. Cox proportional hazards regression, logistical regression, and survival curves were used to assess the association of age, gender, race/ethnicity, insurance, number of partners, and sexually transmitted infection (STI) diagnosis at PrEP initiation with time on PrEP. From August 2016-December 2020, 1,126 people were prescribed PrEP - patients were mostly Black (44.8%) or Latinx (30.4%) and identified as cisgender men (84.6%). Half had no insurance (49.1%), with the remaining patients reporting private (28.9%) or public (21.5%) insurance. Age at PrEP prescription ranged from 15 to 66 with 80% being 20 to 39 years. For the 87.7% (n = 987) of patients who discontinued PrEP, mean PrEP time was 158 days and median was 28 days. The highest rates of discontinuation were observed within the first month with 44.3% discontinuing by day 30, 52.3% by 3 months, and 73.2% by 1 year. Cisgender women, transgender persons, and those younger than 30 years were more likely to discontinue PrEP. Latinx and patients with less than 3 male partners in the last 90 days were less likely to discontinue PrEP. We demonstrated a high level of PrEP uptake among populations disproportionally affected by HIV. Future analyses are needed to examine ways of reducing barriers to PrEP initiation and improving PrEP adherence.

NF-κB modifies the mammalian circadian clock through interaction with the core clock protein BMAL1.

In mammals, the circadian clock coordinates cell physiological processes including inflammation. Recent studies suggested a crosstalk between these two pathways. However, the mechanism of how inflammation affects the clock is not well understood. Here, we investigated the role of the proinflammatory transcription factor NF-κB in regulating clock function. Using a combination of genetic and pharmacological approaches, we show that perturbation of the canonical NF-κB subunit RELA in the human U2OS cellular model altered core clock gene expression. While RELA activation shortened period length and dampened amplitude, its inhibition lengthened period length and caused amplitude phenotypes. NF-κB perturbation also altered circadian rhythms in the master suprachiasmatic nucleus (SCN) clock and locomotor activity behavior under different light/dark conditions. We show that RELA, like the clock repressor CRY1, repressed the transcriptional activity of BMAL1/CLOCK at the circadian E-box cis-element. Biochemical and biophysical analysis showed that RELA binds to the transactivation domain of BMAL1. These data support a model in which NF-kB competes with CRY1 and coactivator CBP/p300 for BMAL1 binding to affect circadian transcription. This is further supported by chromatin immunoprecipitation analysis showing that binding of RELA, BMAL1 and CLOCK converges on the E-boxes of clock genes. Taken together, these data support a significant role for NF-κB in directly regulating the circadian clock and highlight mutual regulation between the circadian and inflammatory pathways.

Climate Change and the Epidemiology of Infectious Diseases in the United States.

The earth is rapidly warming, driven by increasing atmospheric carbon dioxide and other gases that result primarily from fossil fuel combustion. In addition to causing arctic ice melting and extreme weather events, climatologic factors are linked strongly to the transmission of many infectious diseases. Changes in the prevalence of infectious diseases not only reflect the impacts of temperature, humidity, and other weather-related phenomena on pathogens, vectors, and animal hosts but are also part of a complex of social and environmental factors that will be affected by climate change, including land use, migration, and vector control. Vector- and waterborne diseases and coccidioidomycosis are all likely to be affected by a warming planet; there is also potential for climate-driven impacts on emerging infectious diseases and antimicrobial resistance. Additional resources for surveillance and public health activities are urgently needed, as well as systematic education of clinicians on the health impacts of climate change.

Ocular Monkeypox - United States, July-September 2022.

As of October 11, 2022, a total of 26,577 monkeypox cases had been reported in the United States.* Although most cases of monkeypox are self-limited, lesions that involve anatomically vulnerable sites can cause complications. Ocular monkeypox can occur when Monkeypox virus (MPXV) is introduced into the eye (e.g., from autoinoculation), potentially causing conjunctivitis, blepharitis, keratitis, and loss of vision (1). This report describes five patients who acquired ocular monkeypox during July-September 2022. All patients received treatment with tecovirimat (Tpoxx)†; four also received topical trifluridine (Viroptic).§ Two patients had HIV-associated immunocompromise and experienced delays between clinical presentation with monkeypox and initiation of monkeypox-directed treatment. Four patients were hospitalized, and one experienced marked vision impairment. To decrease the risk for autoinoculation, persons with monkeypox should be advised to practice hand hygiene and to avoid touching their eyes, which includes refraining from using contact lenses (2). Health care providers and public health practitioners should be aware that ocular monkeypox, although rare, is a sight-threatening condition. Patients with signs and symptoms compatible with ocular monkeypox should be considered for urgent ophthalmologic evaluation and initiation of monkeypox-directed treatment. Public health officials should be promptly notified of cases of ocular monkeypox. Increased clinician awareness of ocular monkeypox and of approaches to prevention, diagnosis, and treatment might reduce associated morbidity.

Orthopoxvirus Testing Challenges for Persons in Populations at Low Risk or Without Known Epidemiologic Link to Monkeypox - United States, 2022.

Since May 2022, approximately 20,000 cases of monkeypox have been identified in the United States, part of a global outbreak occurring in approximately 90 countries and currently affecting primarily gay, bisexual, and other men who have sex with men (MSM) (1). Monkeypox virus (MPXV) spreads from person to person through close, prolonged contact; a small number of cases have occurred in populations who are not MSM (e.g., women and children), and testing is recommended for persons who meet the suspected case definition* (1). CDC previously developed five real-time polymerase chain reaction (PCR) assays for detection of orthopoxviruses from lesion specimens (2,3). CDC was granted 510(k) clearance for the nonvariola-orthopoxvirus (NVO)-specific PCR assay by the Food and Drug Administration. This assay was implemented within the Laboratory Response Network (LRN) in the early 2000s and became critical for early detection of MPXV and implementation of public health action in previous travel-associated cases as well as during the current outbreak (4-7). PCR assays (NVO and other Orthopoxvirus laboratory developed tests [LDT]) represent the primary tool for monkeypox diagnosis. These tests are highly sensitive, and cross-contamination from other MPXV specimens being processed, tested, or both alongside negative specimens can occasionally lead to false-positive results. This report describes three patients who had atypical rashes and no epidemiologic link to a monkeypox case or known risk factors; these persons received diagnoses of monkeypox based on late cycle threshold (Ct) values ≥34, which were false-positive test results. The initial diagnoses were followed by administration of antiviral treatment (i.e., tecovirimat) and JYNNEOS vaccine postexposure prophylaxis (PEP) to patients' close contacts. After receiving subsequent testing, none of the three patients was confirmed to have monkeypox. Knowledge gained from these and other cases resulted in changes to CDC guidance. When testing for monkeypox in specimens from patients without an epidemiologic link or risk factors or who do not meet clinical criteria (or where these are unknown), laboratory scientists should reextract and retest specimens with late Ct values (based on this report, Ct ≥34 is recommended) (8). CDC can be consulted for complex cases including those that appear atypical or questionable cases and can perform additional viral species- and clade-specific PCR testing and antiorthopoxvirus serologic testing.

Epidemiologic and Clinical Features of Children and Adolescents Aged <18 Years with Monkeypox - United States, May 17-September 24, 2022.

Data on monkeypox in children and adolescents aged <18 years are limited (1,2). During May 17­September 24, 2022, a total of 25,038 monkeypox cases were reported in the United States,† primarily among adult gay, bisexual, and other men who have sex with men (3). During this period, CDC and U.S. jurisdictional health departments identified Monkeypox virus (MPXV) infections in 83 persons aged <18 years, accounting for 0.3% of reported cases. Among 28 children aged 0­12 years with monkeypox, 64% were boys, and most had direct skin-to-skin contact with an adult with monkeypox who was caring for the child in a household setting. Among 55 adolescents aged 13­17 years, most were male (89%), and male-to-male sexual contact was the most common presumed exposure route (66%). Most children and adolescents with monkeypox were non-Hispanic Black or African American (Black) (47%) or Hispanic or Latino (Hispanic) (35%). Most (89%) were not hospitalized, none received intensive care unit (ICU)­level care, and none died. Monkeypox in children and adolescents remains rare in the United States. Ensuring equitable access to monkeypox vaccination, testing, and treatment is a critical public health priority. Vaccination for adolescents with risk factors and provision of prevention information for persons with monkeypox caring for children might prevent additional infections.

Isoform-specific C-terminal phosphorylation drives autoinhibition of Casein Kinase 1.

Casein kinase 1 δ (CK1δ) controls essential biological processes including circadian rhythms and Wnt signaling, but how its activity is regulated is not well understood. CK1δ is inhibited by autophosphorylation of its intrinsically disordered C-terminal tail. Two CK1 splice variants, δ 1 and δ 2 , are known to have very different effects on circadian rhythms. These variants differ only in the last 16 residues of the tail, referred to as the extreme C-termini (XCT), but with marked changes in potential phosphorylation sites. Here we test if the XCT of these variants have different effects in autoinhibition of the kinase. Using NMR and HDX-MS, we show that the δ 1 XCT is preferentially phosphorylated by the kinase and the δ 1 tail makes more extensive interactions across the kinase domain. Mutation of δ1 -specific XCT phosphorylation sites increases kinase activity both in vitro and in cells and leads to changes in circadian period, similar to what is reported in vivo. Mechanistically, loss of the phosphorylation sites in XCT disrupts tail interaction with the kinase domain. δ1 autoinhibition relies on conserved anion binding sites around the CK1 active site, demonstrating a common mode of product inhibition of CK1δ . These findings demonstrate how a phosphorylation cycle controls the activity of this essential kinase.

Ureaplasma septic polyarthritis in a young woman with neuromyelitis optica receiving rituximab.

We report a case of septic polyarthritis caused by Ureaplasma urealyticum in a woman with neuromyelitis optica who was receiving rituximab. Her case exemplifies some of the unique characteristics of invasive Ureaplasma infections that can lead to delayed diagnosis as well as treatment challenges including recurrence following antibiotic discontinuation.

Cigarette smoke combined with Toll-like receptor 3 signaling triggers exaggerated epithelial regulated upon activation, normal T-cell expressed and secreted/CCL5 expression in chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is characterized by persistent mucosal inflammation and frequent exacerbations. OBJECTIVE: To determine whether innate epithelial responses to cigarette smoke or bacterial or viral pathogens may be abnormal in CRS leading to an inappropriate inflammatory response. METHODS: Primary nasal epithelial cells (PNECs) were grown from middle turbinate biopsies of 9 healthy controls and 11 patients with CRS. After reaching 80% to 90% confluence, PNECs were exposed to medium or cigarette smoke extract (CSE) 5% (vol/vol) for 1 hour, washed, then stimulated with staphylococcal lipoteichoic acid, LPS, or double-stranded RNA (dsRNA). After 24 hours, gene expression was quantified by QRT-PCR. RESULTS: At baseline, PNECs revealed elevated TNF-alpha and growth-related oncogene-alpha (a C-X-C chemokine)/CXCL1 (GRO-alpha) (4-fold increase, P = .02; and 16-fold increase, P = .004, respectively) in subjects with CRS compared with controls with normal levels of IL-1beta, IL-6, IL-8/CXCL8, human beta-defensin-2, monocyte chemoattractant protein 2/CCL8, monocyte chemoattractant protein 3/CCL7, and regulated upon activation, normal T-cell expressed and secreted (RANTES)/CCL5. Immunostaining of nasal biopsies, however, revealed comparable epithelial staining for TNF-alpha, GRO-alpha, and RANTES. There were no differences in mRNA induction by CSE, TNF-alpha, lipoteichoic acid, LPS, or dsRNA alone. The combination of CSE+dsRNA induced exaggerated RANTES (12,115-fold vs 1500-fold; P = .03) and human beta-defensin-2 (1120-fold vs 12.5-fold; P = .05) in subjects with CRS. No other genes were differentially induced. Furthermore, CSE+dsRNA induced normal levels of IFN-beta, IFN-lambda1, and IFN-lambda2/3 mRNA in subjects with CRS. CONCLUSION: Cigarette smoke extract plus dsRNA induces exaggerated epithelial RANTES expression in patients with CRS. We propose that an analogous response to cigarette smoke plus viral infection may contribute to acute exacerbations and eosinophilic mucosal inflammation in CRS.