The

The Vibriofischeri luminescence (lux) genes are regulated by the 250-amino-acid-residue LuxR protein and a V. fischeri metabolite termed autoinducer. The V. fischeri lux regulon consists of two divergently transcribed

Human cytomegalovirus (HCMV) latency and reactivation rely on a complex interplay between cellular differentiation, cell signaling pathways, and viral gene functions. HCMV reactivation in dendritic cells (DCs) is triggered by IL-6 and extracellular signal-regulated kinase (ERK)–mitogen-activated protein kinase signaling. However, activation of the same pathway fails to reactivate HCMV in other myeloid cell types, despite this signaling axis being active in those cells. We hypothesized that IL-6–induced ERK activation initiates the changes in chromatin structure required for viral reactivation but that a concomitant signal is necessary to complete the changes in chromatin structure required for gene expression to occur. Using a differential phosphoproteomics approach in cells that do or do not support IL-6–induced viral reactivation, we identified the concomitant activation of an Src family kinase (SFK), hematopoietic cell kinase (HCK), specifically in DCs in response to IL-6. Pharmacological and genetic inhibition of HCK activity indicated that HCK is required for HCMV reactivation. Furthermore, the HCK/SFK activity was linked to recruitment of the monocytic leukemia zinc finger protein (MOZ) histone acetyltransferase to the viral promoter, which promoted histone acetylation after ERK-mediated histone phosphorylation. Importantly, pharmacological and genetic inhibition of MOZ activity prevented reactivation. These results provide an explanation for the selective activation of viral gene expression in DCs by IL-6, dependent on concomitant SFK and ERK signaling. They also reveal a previously unreported role for SFK activity in the regulation of chromatin structure at promoters in eukaryotic cells via MOZ histone acetyltransferase activity.

ImportanceLandmark studies showed that partial clinical remission in new-onset type 1 diabetes is associated with reduced prevalence of long-term complications, but early clinical indicators of this favorable outcome are poorly characterized.AimTo determine if there were any differences in lipid parameters, especially LDL-cholesterol, between remitters and non-remitters 4 to 5 years after the diagnosis of type 1 diabetes after controlling for hemoglobin A1c, body mass index, and pubertal status.Subjects and methodsA longitudinal retrospective cohort study of 123 subjects of mean age 11.9 ± 2.9 years, [male 11.7 ± 2.9 years, (n = 55); female 12.0 ± 2.9 years, (n = 68), p = 0.60] with type 1 diabetes of 4–5 years duration. Anthropometric and biochemical data were collected at the 4th or 5th year after diagnosis in line with the American Diabetes Association recommendation to initiate screening for complications in children either at the beginning of puberty or 4–5 years after diagnosis. Puberty was defined by Tanner stages II-V. Partial clinical remission was defined by the gold-standard insulin-dose adjusted hemoglobin A1c (IDAA1c) of ≤9.ResultsThere were 44 (35.8%) remitters (age 13.0 ± 2.5y; male 52.3%). Both the total cholesterol and LDL-cholesterol were significantly lower in remitters compared to non-remitters: LDL-C: 78.8 ± 28.7 mg/dL vs. 91.6 ± 26.5 mg/dL, p = 0.023; and total cholesterol: 151.5 ± 32.6 mg/dL vs. 167.0 ± 29.6 mg/dL, p = 0.015. Other lipid fractions were similar between the groups. There were no differences between the groups for glycemic control, body mass index z score, thyroid function, celiac disease occurrence, or vitamin D status. A greater number of remitters were in puberty compared to non-remitters (86.4% vs. 60.8%, p = 0.006). LDL-C concentration was similar in prepubertal remitters vs. non-remitters (p = 0.93), but was significantly lower in remitters in puberty compared to non-remitters in puberty (p = 0.018) after adjusting for age and duration of diabetes.ConclusionsChildren with type 1 diabetes who underwent a honeymoon phase had significantly lower LDL cholesterol 5 years after diagnosis. This early divergence in lipidemia may explain the dichotomy in the prevalence of long-term complication in type 1 diabetes between remitters and non-remitters. It also offers a pathway for targeted lipid monitoring in type 1 diabetes, by establishing non-remission as a non-modifiable risk factor for vascular complication in type 1 diabetes.