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Skin histopathology of the affected mice. Skin of an affected mouse at age 16 weeks showed hyperkeratosis (arrow) and hyperplasia of the epidermis and thin dermis layer with scanty subcutaneous adipose tissue (A) when compared to a wild-type mouse (B). The hair follicles contained no hair shafts and their upper portions were dilated and filled with keratinized materials in a mutant mouse (C) as compared to the normal hair follicles in a wild-type mouse (D). (H&E, Bar = 200 µm in A and B; 100 µm in C and D).
Source publication
Protein palmitoylation has emerged as an important mechanism for regulating protein trafficking, stability, and protein-protein interactions; however, its relevance to disease processes is not clear. Using a genome-wide, phenotype driven N-ethyl-N-nitrosourea-mediated mutagenesis screen, we identified mice with failure to thrive, shortened life spa...
Citations
... The objectives of the present study were to identify variants associated with hereditary AA-amyloidosis in mixed Siamese/Oriental cats based on Illumina Infinium Feline 63 K iSelect DNA array data of cases and controls with multi-locus GWAS models. Within the genomic regions of these variants, we searched for putative functional candidate genes that have previously been reported to be associated with hereditary forms of amyloidosis in humans and mice [15,[18][19][20]. ...
... Interestingly, a mutation in ZDHHC13 caused a severe phenotype in mice including systemic AA-and AL-amyloidosis. Therefore, a variant in ZDHHC13 might also play a role in systemic AA-amyloidosis in cats [20]. ...
AA-amyloidosis in Siamese and Oriental shorthair cats is a lethal condition in which amyloid deposits accumulate systemically, especially in the liver and the thyroid gland. The age at death of affected cats varies between one and seven years. A previous study indicated a complex mode of inheritance involving a major locus. In the present study, we performed a multi-locus genome-wide association study (GWAS) using five methods (mrMLM, FASTmrMLM, FASTmrEMMA, pLARmEB and ISIS EM-BLASSO) to identify variants associated with AA-amyloidosis in Siamese/Oriental cats. We genotyped 20 affected mixed Siamese/Oriental cats from a cattery and 48 healthy controls from the same breeds using the Illumina Infinium Feline 63 K iSelect DNA array. The multi-locus GWAS revealed eight significantly associated single nucleotide polymorphisms (SNPs) on FCA A1, D1, D2 and D3. The genomic regions harboring these SNPs contain 55 genes, of which 3 are associated with amyloidosis in humans or mice. One of these genes is SAA1, which encodes for a member of the Serum Amyloid A family, the precursor protein of Amyloid A, and a mutation in the promotor of this gene causes hereditary AA-amyloidosis in humans. These results provide novel knowledge regarding the complex genetic background of hereditary AA-amyloidosis in Siamese/Oriental cats and, therefore, contribute to future genomic studies of this disease in cats.
... Protein palmitoylation has emerged as a critical mechanism regulating protein stability, trafficking, and protein-protein interactions, which is involved in OP [23]. APT1 is a cytosolic depalmitoylase that can depalmitoylate proteins from membranes [10]. ...
Objective:
Senile osteoporosis (SOP) is an aging-related disease. The depalmitoylating enzyme Acyl-protein thiesterase1 (APT1) is involved in disease regulation. This study explored the mechanism of APT1 in SOP.
Methods:
Eight-week-old SAMP6 mice were selected as SOP models and SAMR1 mice were controls, while osteoblasts were isolated from the femoral surface-soft tissues of SOP and control mice as in vitro models. Mouse femur morphological, bone mineral density (BMD), femur maximum elastic stress and maximum load, and APT1 expression were detected by HE staining, X-ray bone densitometer, material testing machine, and RT-qPCR and Western blot (WB). Osteoprotegrin (OPG)-labeled osteoblasts and APT1 localization in bone tissues were detected by immunohistochemical staining. APT1 expression was promoted in SOP mice by tail vein injection of APT1 lentivirus or promoted/silenced in osteoblasts by transfection of pcDNA3.1-APT1 overexpression or si-APT1 plasmids. SOP mouse osteoblast differentiation (OD), OD-related protein levels, osteoblast proliferation, BMPR1a palmitoylation level, and BMP/Smad pathway were detected by alizarin red staining, ALP activity detection, WB, CCK-8, and IP-ABE method. The effects of the pathway inhibitor LDN-193189 on OD were detected.
Results:
APT1 was under-expressed in osteoblasts of bone tissue in SOP mice and mainly localized in osteoblasts. SOP mice manifested increased bone marrow cavity and bone trabecular space, thinned trabecular bone, decreased BMD, maximum elastic stress, maximum load, and reduced OPG-positive osteoblasts in bone tissues, which were averted by APT1 overexpression, thus alleviating SOP. APT1 overexpression increased osteoblast calcium nodules, ALP activity, OD-related protein levels, and cell proliferation. In mechanism, APT1 overexpression inhibited BMPR1a palmitoylation in SOP mouse osteoblasts and activated the BMP/Smad pathway, thus promoting OD.
Conclusion:
APT1 activated the BMP/Smad pathway and promoted OD by regulating BMPR1a depalmitoylation, thus alleviating mouse SOP.
... A number of proteins were palmitoylated in differentiating osteoblasts, and pharmacological inhibition of palmitoylation hindered osteoblast differentiation and mineralization [18]. Consistent with these in vitro results, mice with Zdhhc13 deficiency exhibited osteoporosis [19,20]. The further mechanistic study revealed that ZDHHC13 promoted bone formation in part by palmitoylating MT1-MMP [19]. ...
Background:
Excessive osteoclast formation disrupts bone homeostasis, thereby significantly contributing to pathological bone loss associated with a variety of diseases. Protein S-palmitoylation is a reversible post-translational lipid modification catalyzed by ZDHHC family of palmitoyl acyltransferases, which plays an important role in various physiological and pathological processes. However, the role of palmitoylation in osteoclastogenesis has never been explored. Consequently, it is unclear whether this process can be targeted to treat osteolytic bone diseases that are mainly caused by excessive osteoclast formation.
Materials and methods:
In this study, we employed acyl-biotin exchange (ABE) assay to reveal protein S-palmitoylation in differentiating osteoclasts (OCs). We utilized 2-bromopalmitic acid (2-BP), a pharmacological inhibitor of protein S-palmitoylation, to inhibit protein palmitoylation in mouse bone marrow-derived macrophages (BMMs), and tested its effect on receptor activator of nuclear factor κβ ligand (RANKL)-induced osteoclast differentiation and activity by TRAP staining, phalloidin staining, qPCR analyses, and pit formation assays. We also evaluated the protective effect of 2-BP against estrogen deficiency-induced bone loss and bone resorption in ovariectomized (OVX) mice using μCT, H&E staining, TRAP staining, and ELISA assay. Furthermore, we performed western blot analyses to explore the molecular mechanism underlying the inhibitory effect of 2-BP on osteoclastogenesis.
Results:
We found that many proteins were palmitoylated in differentiating OCs and that pharmacological inhibition of palmitoylation impeded RANKL-induced osteoclastogenesis, osteoclast-specific gene expression, F-actin ring formation and osteoclastic bone resorption in vitro, and to a lesser extent, osteoblast formation from MC3T3-E1 cells. Furthermore, we demonstrated that administration of 2-BP protected mice from ovariectomy-induced osteoporosis and bone resorption in vivo. Mechanistically, we showed that 2-BP treatment inhibited osteoclastogenesis partly by downregulating the expression of c-Fos and NFATc1 without overtly affecting RANKL-induced activation of osteoclastogenic AKT, MAPK, and NF-κB pathways.
Conclusion:
Pharmacological inhibition of palmitoylation potently suppresses RANKL-mediated osteoclast differentiation in vitro and protects mice against OVX-induced osteoporosis in vivo. Mechanistically, palmitoylation regulates osteoclast differentiation partly by promoting the expression of c-Fos and NFATc1. Thus, palmitoylation plays a key role in promoting osteoclast differentiation and activity, and could serve as a potential therapeutic target for the treatment of osteoporosis and other osteoclast-related diseases.
The translational potential of this article:
The translation potential of this article is that we first revealed palmitoylation as a key mechanism regulating osteoclast differentiation, and therefore provided a potential therapeutic target for treating osteolytic bone diseases.
... Further, in the presence of mHTT with an expanded polyQ tract in the YAC128 HD mouse model, there is reduced HTT palmitoylation and reduced interaction between HTT and ZDHHC17 (Singaraja et al., 2002;Huang et al., 2004;Yanai et al., 2006). In a mouse model expressing truncated ZDHHC13 that retains the N-terminal ankyrin repeat, mice have abnormalities in hair, skin, and bone, as well as reduced survival and increased amyloidosis, indicating a role of ZDHHC13 in regulating essential functions in multiple tissue and cell types, including neurons, epithelial, and bone (Saleem et al., 2010). Interestingly, a less severe phenotype is linked to Zdhhc13 knockout. ...
One of the first molecular events in neurodegenerative diseases, regardless of etiology, is protein mislocalization. Protein mislocalization in neurons is often linked to proteostasis deficiencies leading to the build-up of misfolded proteins and/or organelles that contributes to cellular toxicity and cell death. By understanding how proteins mislocalize in neurons, we can develop novel therapeutics that target the earliest stages of neurodegeneration. A critical mechanism regulating protein localization and proteostasis in neurons is the protein-lipid modification S-acylation, the reversible addition of fatty acids to cysteine residues. S-acylation is more commonly referred to as S-palmitoylation or simply palmitoylation, which is the addition of the 16-carbon fatty acid palmitate to proteins. Like phosphorylation, palmitoylation is highly dynamic and tightly regulated by writers (i.e., palmitoyl acyltransferases) and erasers (i.e., depalmitoylating enzymes). The hydrophobic fatty acid anchors proteins to membranes; thus, the reversibility allows proteins to be re-directed to and from membranes based on local signaling factors. This is particularly important in the nervous system, where axons (output projections) can be meters long. Any disturbance in protein trafficking can have dire consequences. Indeed, many proteins involved in neurodegenerative diseases are palmitoylated, and many more have been identified in palmitoyl-proteomic studies. It follows that palmitoyl acyl transferase enzymes have also been implicated in numerous diseases. In addition, palmitoylation can work in concert with cellular mechanisms, like autophagy, to affect cell health and protein modifications, such as acetylation, nitrosylation, and ubiquitination, to affect protein function and turnover. Limited studies have further revealed a sexually dimorphic pattern of protein palmitoylation. Therefore, palmitoylation can have wide-reaching consequences in neurodegenerative diseases.
... Osteoporosis can also be proven in the trabecular femur by looking at the parameters of decreasing bone volume density (BV/TV) and bone mineral density (BMD). 28 The percentage of bone density and osteoblast cell levels differed significantly between the healthy and negative groups (P<0.05), it could be seen that the glucocorticoid can decrease the percentage of bone density and osteoblast cell levels. The dose treatment group then demonstrated the opposite effect, increasing the percentage of bone density and osteoblast cell levels. ...
Background:
Low bone mass accompanied by microarchitectural alterations in the bone that cause fragility fractures is known as secondary osteoporosis and occurs when there is an underlying condition or medication present. Eleutherine bulbosa bulb extract has been shown to affect bone because of its content, which can help osteoblast differentiation and inhibit osteoclast differentiation.
Objective:
This study aimed to assess the effects of 70% ethanol extract of E. bulbosa Bulbs (EBE) from Pasuruan-East Java on blood calcium levels, osteoblast cell count, and bone density of trabecular femur in osteoporosis rats.
Methods:
Six groups of 30 female Wistar rats were created. There were no test materials offered to the healthy group; the negative group received 0.5% CMC; the positive group received alendronate 0.9 mg/kg BW; and the dose group received 30, 60, and 120 mg/kg BW. Glucocorticoid (Dexamethasone) 0.1015 mg/kg BW/day induction was given to all groups except the healthy group to create osteoporosis rats for approximately four weeks. Then they were given oral therapy for approximately 28 days. Followed by the determination of blood calcium levels, the number of osteoblast cells, and bone density of the rat femur trabecular.
Results:
The result showed that E. bulbosa bulbs extract could raise blood calcium levels and bone density percentage at doses of 60 and 120 mg/kg BW, as well as raise osteoblast cell levels at doses of 120 mg/kg BW.
Conclusions:
The findings indicate that E.bulbosa bulb extract is a potential complementary medicine for osteoporosis.
... zDHHC5 mutant mice show partial embryonic lethality (Li et al., 2010) while zDHHC8 knockout mice displayed decreased synapse, spine, and dendritic complexity (Mukai et al., 2008). zDHHC13 mutants show decreased lifespan, decreased size, osteoporosis, and muscle loss (Saleem et al., 2010) and zDHHC17 mutant mice resulted in weight loss and decreased brain size (Singaraja et al., 2011). ...
... In the present study, the hair follicles contained no hair shafts and their upper portions were dilated and filled with keratinised materials. Saleem et al 37 reported similar results in the histopathology of Zdhhc13 mutant mice. ...
Alopecia is a common disease that affects both physiological and psycho-social interaction in humans and environmental pollution contributes to a greater extent. People who live in arsenic polluted regions such as mines and nearby areas are unaware of topical arsenic exposure and its effects. Moreover, the topical application of arsenic on mice skin is not studied yet. Studies are needed to elaborate on the mode of action of arsenic on skin and hair. Thus, the present study aims to characterise the topical application of sodium arsenite (As 3+)(14.6 mg/kg bw) on C57BL mice. After the experiment, skin tissues were excised, processed, sectioned and stained with haematoxylin and eosin. The effect of arsenic exposure is manifested by erosion of epidermis, epithelial hyperplasia, hyperkeratosis, lipid peroxidation, sebaceous gland degeneration and inflammatory infiltration of immune cells. The hair shaft is replaced by the keratinised substance in the affected hair follicles. The results revealed that arsenic is detrimental to the healthy growth of skin and hair.
... In the present study, the hair follicles contained no hair shafts and their upper portions were dilated and filled with keratinised materials. Saleem et al 37 reported similar results in the histopathology of Zdhhc13 mutant mice. ...
Alopecia is a common disease that affects both physiological and psycho-social interaction in humans and environmental pollution contributes to a greater extent. People who live in arsenic polluted regions such as mines and nearby areas are unaware of topical arsenic exposure and its effects. Moreover, the topical application of arsenic on mice skin is not studied yet. Studies are needed to elaborate on the mode of action of arsenic on skin and hair. Thus, the present study aims to characterise the topical application of sodium arsenite (As3+)(14.6 mg/kg bw) on C57BL mice. After the experiment, skin tissues were excised, processed, sectioned and stained with haematoxylin and eosin. The effect of arsenic exposure is manifested by erosion of epidermis, epithelial hyperplasia, hyperkeratosis, lipid peroxidation, sebaceous gland degeneration and inflammatory infiltration of immune cells. The hair shaft is replaced by the keratinised substance in the affected hair follicles. The results revealed that arsenic is detrimental to the healthy growth of skin and hair.
... Among these genes, we found two that may be linked to manifesting diminutive size. Mutations of ZDHHC13 (PSG in marmosets) in mice causes post-translational lipid modification, resulting in weight loss and reduced bone mineral density 42 . FGFR1 (PSG in New World monkeys) regulates a feedback signal to control the rate of differentiation of osteoblasts 43 , and mutations cause autosomal dominant skeletal disorder 44 . ...
The accurate and complete assembly of both haplotype sequences of a diploid organism is essential to understanding the role of variation in genome functions, phenotypes, and diseases1. Here, using a trio-binning approach, we present a high-quality, diploid reference genome, with both haplotypes assembled independently at the chromosome level, for the common marmoset (Callithrix jacchus), an important primate model system widely used in biomedical research2,3. The full heterozygosity spectrum between the two haplotypes involves 1.36% of the genome, much higher than the 0.13% indicated by the standard single nucleotide heterozygosity estimation alone. The de novo mutation rate is 0.43 × 10-8 per site per generation, where the paternal inherited genome acquired twice as many mutations as the maternal. Our diploid assembly enabled us to discover a recent expansion of the sex differentiated region and unique evolutionary changes in the marmoset Y chromosome. Additionally, we identified many genes with signatures of positive selection that might have contributed to the evolution of Callithrix biological features. Brain related genes were highly conserved between marmosets and humans, though several genes experienced lineage-specific copy number variations or diversifying selection, providing important implications for the application of marmosets as a model system.
... Essential and unique roles for zDHHC proteins have been identified using zDHHC-deficient mouse models [30]. Phenotypes observed include neurodevelopmental deficits, defective learning and memory and neurodegeneration [31][32][33][34]. Accordingly, there is significant interest in understanding the mechanism and regulation of zDHHC enzymes. ...
... A site-specific quantitative mass spectrometry approach was applied to characterize the mouse liver palmitoylome in wild-type and zDHHC13deficient mice. Prior studies had demonstrated that this mouse model displays severe phenotypes, including amyloidosis, alopecia and osteoporosis [33]. The finding that zDHHC13deficient mice also have an abnormal liver function, lipid abnormalities and hypermetabolism led investigators to identify substrates that might contribute to liver pathophysiology [85]. ...
Protein palmitoylation is the post-translational attachment of fatty acids, most commonly palmitate (C16 : 0), onto a cysteine residue of a protein. This reaction is catalysed by a family of integral membrane proteins, the zDHHC protein acyltransferases (PATs), so-called due to the presence of an invariant Asp–His–His–Cys (DHHC) cysteine-rich domain harbouring the catalytic centre of the enzyme. Conserved throughout eukaryotes, the zDHHC PATs are encoded by multigene families and mediate palmitoylation of thousands of protein substrates. In humans, a number of zDHHC proteins are associated with human diseases, including intellectual disability, Huntington's disease, schizophrenia and cancer. Key to understanding the physiological and pathophysiological importance of individual zDHHC proteins is the identification of their protein substrates. Here, we will describe the approaches and challenges in assigning substrates for individual zDHHCs, highlighting key mechanisms that underlie substrate recruitment.
