14‐3‐3β isoform is specifically acetylated at Lys51 during differentiation to the osteogenic lineage

Abstract

The 14-3-3 protein family binds and regulates hundreds of serine/threonine phosphorylated proteins as an essential component of many signaling networks. Specific biological functions are currently been discovered for each of its seven isoforms in mammals. These proteins have been traditionally considered unregulated; however, its acetylation in an essential lysine residue, causing its inactivation, was recently published. Here, we studied the acetylation state of this lysine 49/51 during the osteogenic differentiation of human adipose-derived stem cells. We found that during this process, the levels of 14-3-3β (but not its isoform 14-3-3γ) acK49/51 increase, representing the first report linking this PTM to a specific isoform and a cellular process. Our results suggested that this posttranslational modification could be catalyzed by the HBO1 acetyltransferase, as overexpression of HBO1 increased specifically 14-3-3 acK49/51 acetylation. Acetylated 14-3-3 proteins are located primarily in the nucleus, where their active state has been described to bind H3 histones and many transcription factors. The inhibition of the expression of different isoforms showed that the specific silencing of the 14-3-3β gene, but not γ, increased significantly the osteogenic potential of the cells. This result correlated to the increase in acetylation of 14-3-3β Lys 49/51 during osteogenesis. The possible role of this PTM in osteogenesis is discussed.

Chronic exercise remodels the lysine acetylome in the mouse hippocampus

“…By regulating their targets, 14-3-3 proteins play a role in neurogenesis, neuronal migration and differentiation, synaptogenesis and dopamine synthesis (Antunes et al, 2022). The biological relevance of acetylation has been investigated in some 14-3-3 isoforms (Choudhary et al, 2009;Aghazadeh et al, 2014;Frontini-Lopez et al, 2021); however, we identified different acetylated site on 14-3-3 gamma. Therefore, the function of acetylated 14-3-3 gamma in Hippo pathway as well as other DAPs with hippocampal neurogenesis during exercise remains to be elucidated.…”

Human adipose mesenchymal stromal cells growing into PCL‐nHA electrospun scaffolds undergo hypoxia adaptive ultrastructural changes

“…[ 18 ] hAD‐MSCs were cultured and incubated with ODM as previously described. [ 14,19 ] Briefly, for all experiments, hAD‐MSCs were seeded on tissue culture treated wells, coverslips, or previously sterilized (UV light 20 min) scaffolds at 40,000 cells/cm 2 , and grown in standard culture conditions (DMEM, 10% FBS, 100 U/mL penicillin/streptomycin, 37°C, 5% CO 2 ) for 7 days. Isolations from three independent donors in young passages (2 to 4) were used.…”

“…The material was processed to obtain the hAD-MSCs from the stromal vascular fraction, and cell characterization was conducted by flow cytometry analysis (CD105, CD90, CD73 positive markers, and CD45, CD34, CD11b, CD19, HLA-DR negative markers) and by differentiation to adipogenic and osteogenic lineages as in Gojanovich et al [18] hAD-MSCs were cultured and incubated with ODM as previously described. [14,19] Briefly, for all experiments, hAD-MSCs were seeded on tissue culture treated wells, coverslips, or previously sterilized (UV light 20 min) scaffolds at 40,000 cells/cm 2 , and grown in standard culture conditions (DMEM, 10% FBS, 100 U/mL penicillin/streptomycin, 37 • C, 5% CO 2 ) for 7 days. Isolations from three independent donors in young passages (2 to 4) were used.…”

“…Osteogenic differentiation of hAD-MSCs was induced with a drug cocktail containing 10 mM β-glycerophosphate, 0.1 μM dexamethasone, and 50 μg/mL 2-phospho-L-ascorbic acid for 7 days, based on our previously reported information. [12,14,19]…”