The Histone Acetyltransferase p300 Regulates the Expression of Pluripotency Factors and Odontogenic Differentiation of Human Dental Pulp Cells

Abstract

p300 is a well-known histone acetyltransferase (HAT) and coactivator that plays vital roles in many physiological processes. Despite extensive research on the involvement of p300 in the regulation of transcription in numerous cell lines, the roles of this protein in regulating pluripotency genes and odontogenic differentiation in human dental pulp cells (HDPCs) are poorly understood. To address this issue, we investigated the expression of OCT4, NANOG and SOX2 and the proliferation and odontogenic differentiation capacity of HDPCs following p300 overexpression. We found that p300 overexpression did not overtly affect the ability of HDPCs to proliferate. The overexpression of p300 upregulated the promoter activity and the mRNA and protein expression of NANOG and SOX2. The HAT activity of p300 appeared to partially mediate the regulation of these factors; indeed, when a mutant form of p300 lacking the HAT domain was overexpressed, the promoter activity and expression of NANOG and SOX2 decreased relative to p300 overexpression but was greater than in the control. Furthermore, we demonstrated that the mRNA levels of the odontogenic marker genes dentine matrix protein-1 (DMP-1), dentin sialophosphoprotein (DSPP), dentin sialoprotein (DSP), osteopontin (OPN) and osteocalcin (OCN) were significantly decreased in HDPCs overexpressing p300 cultured under normal culture conditions and increased in HDPCs inducted to undergo odontogenic differentiation. This finding was further confirmed by measuring levels of alkaline phosphatase (ALP) activity and assessing the formation of mineralized nodules. The HAT activity of p300 had no significant effect on odontogenic differentiation. p300 was recruited to the promoter regions of OCN and DSPP and might be acting as a coactivator to increase the acetylation of lysine 9 of histone H3 of OCN and DSPP. Collectively, our results show that p300 plays an important role in regulating the expression of key pluripotency genes in HDPCs and modifying odontogenic differentiation.

Wnt-3a Induces Epigenetic Remodeling in Human Dental Pulp Stem Cells

“…Another report showed that a short pre-application of 5-aza-dC for 24 h increased the responsiveness of DPSCs to osteogenic differentiation protocols [79], a similar result to the one obtained after preconditioning DPSCs for 48 h with BIO or WNT-3A, as we showed in our own previous research [13]. Regarding other epigenetic marks such as acetylation, it was reported that p300, a well-known histone acetyltransferase, also played an important role in maintaining the stemness of DPSCs [80]. Moreover, different types of histone deacetylases or HDACs such as HDAC1, HDAC2, HDAC3, HDAC4, and HDAC9 act as important accelerators of odontoblast differentiation [81][82][83] and a similar effect has been described for histone demethylases like KDM6B, which removes H3K27me3 tags [84].…”

Teeth‐derived stem cells: A source for cell therapy

“…Increasing evidence revealed that deregulation of miRNAs is associated with initiation and progression of many diseases such as cancer, stroke, cardiovascular diseases, depression, and regenerative diseases (Gholamin et al, ; Hoseini et al, ; Jafari et al, ; Keshavarzi et al, ; Khanmohammadi et al, ; Mirzaei et al, ; Mirzaei, ; Moridikia et al, ; Mirzaei et al, ; Mirzaei et al, ; Rabieian et al, ; Tavakolizadeh et al, ). MiRNAs could be involved in the regulation of several genes related to dental stem cells fate (Wang et al, ). Hence, identification of them could help to better understand the underlying mechanisms involved in dental stem cell fate.…”

“…Hence, identification of them could help to better understand the underlying mechanisms involved in dental stem cell fate. Several studies revealed that miRNAs play a key role in activation or inactivation of many genes related to cell differentiation of dental tissue stem cells such as angiogenic differentiation, osteogenic, and odontogenic (Wang et al, ). MiRNAs have different expressions in various cell populations (Fathullahzadeh et al, ; Mohammadi et al, ; Mirzaei et al, ; Mirzaei et al, ; Salarinia et al, ; Saadatpour et al, ).…”

Epigenetics: general characteristics and implications for oral health

“… 25 , 26 , 38 Histone acetylations and deacetylations play crucial roles in regulations of gene expression and may promote pulp repair and regeneration. 25 , 26 , 38 , 39 , 40 Therefore, studies on epigenetic regulations in restorative dentistry have grown in importance.…”

“… 13 In addition, histone acetyltransferase and non-coding RNAs may influence odontogenic differentiation. 40 , 42 Epigenetic factors present at each developmental stage can affect the developmental processes. 13 Thus, some studies have proposed that epigenetic events during tooth development may lead to dental differences in monozygotic twins having identical genotypes.…”