Characterization of the human mucin 5AC promoter and its regulation by the histone acetyltransferase P300

Abstract

Histone acetylation is important in the modification of gene transcription in asthma and is regulated by histone acetyltransferases (HATs). P300 (P300 HAT) is an enzyme that is able to acetylate a wide variety of proteins. The modification of core histones can further regulate gene transcription, cell proliferation and other cell processes. Airway mucus hypersecretion is one of the most serious pathophysiological symptoms of chronic airway inflammatory diseases, and the human mucin 5AC (MUC5AC) gene has been reported to be a major component of respiratory secretions related to asthma and chronic obstructive pulmonary disease. In the present study, the 5′ sequence of the human MUC5AC gene with a 1,348-bp DNA sequence was amplified from human A549 cells genomic DNA by polymerase chain reaction (PCR), and the product of the PCR was sequenced. By promoter deletion analysis, five promoter segments with different lengths were amplified by PCR. The products were identified by DNA sequencing and the six promoter segments were inserted into pGL3-enhancer vectors. The core promoter area was identified with a series of 5′ deletion promoter plasmids using luciferase reporter assays. MUC5AC promoter activity, and the mRNA and protein expression levels of MUC5AC were observed in P300 wild-type, P300 mutant, P300 small interfering RNA and P300 control groups. The results showed that the core promoter area of MUC5AC was located within the −935/+48 region and that P300 reduced the expression of MUC5AC in A549 cells.

Current understanding of epigenetics role in melanoma treatment and resistance

“…The regulation of chromatin structure and remodeling can be triggered by both acetylation and deacetylation, which have been considered as post-translational modifications (PTMs) identified in different developmental steps during cancers [ 109 ]. Histone acetyltransferases neutralize the positive charge of histones and diminish the tight-binding between the negatively charged DNA and the histone [ 114 ]. This acetylation changes a closed heterochromatin structure into open chromatin, thus promoting greater chromatin accessibility and gene transcription [ 115 ].…”

Mucins as a New Frontier in Pulmonary Fibrosis

“…However, reduced expression of MUC5AC in goblet cells from IPF lung lesions has been noted in comparison to controls [57,58]. Histone acetyltransferase p300, which is upregulated in IPF bronchial epithelial cells [97], reduces the expression of MUC5AC [98], as does the IPF-activated developmental Notch signalling pathway [99], which can directly downregulate MUC5AC promoter activity [100]. Furthermore, autophagy, which is defective in IPF [101,102,103], has been reported to increase the secretion of MUC5AC by promoting the phosphorylation of c-Jun N-terminal kinase (JNK) and c-Jun in patients with chronic rhinosinusitis [104].…”

A lentiviral toolkit to monitor airway epithelial cell differentiation using bioluminescence

“…Next, we aimed to use this vector to produce cell type-specific promoter-reporter constructs for the main cell types of the pseudostratified airway epithelium (Figure 1B); basal, mucosecretory and ciliated cells. We identified sequences with literature evidence of promoter activity that were upstream of the transcription start sites of the TP63, MUC5AC and FOXJ1 genes, respectively (22)(23)(24)(25)(26). Each promoter sequence was isolated by PCR of genomic DNA with primer pairs that included the XhoI and BamHI sequences.…”