Project description:The Wiskott-Aldrich Syndrome Protein (WASP) family is known for its participation in cytoskeleton reorganization (Marchand et al., 2001 and Jia et al., 2010). In 2007, the human subtelomeric MGC52000 genes were renamed as Wiskott-Aldrich Syndrome Protein and SCAR Homolog (WASH). Human WASH proteins are part of the WASP protein family and colocalize with actin in cells and promote Arp2/3-dependent actin polymerization in vitro (Linardopoulou et al., 2007). WASH multiprotein complex consists of seven subunits: notable to mention Strumpelin and Was Protein Family Homolog (WASH)-interacting protein (SWIP), which is encoded by KIAA1033/WASHC4 gene, FAM21 and Arp2/3. The Arp2/3 dependent actin polymerization from G-actin to F-actin is an important step in regulation of the cytoskeleton, enabling multiple endosomal transport processes (Kelleher et al., 1995 and Derivery et al., 2010). Linardopoulou and colleagues have also shown in an animal model (Drosophila), that the single WASH ortholog is essential for viability (Linardopoulou et al., 2007), strengthening the concept, that WASHC4 plays a crucial role in muscle cell integrity and function. A link between autosomal recessive intellectual disability (ARID) and mutations in the KIAA1033/WASHC4 gene was first recognized in 2011 by Ropers and colleagues. Very recently, Assoum and colleagues reported three additional patients (from two unrelated families) with syndromic ID. Two of them being sisters (8 and 6 years), both presenting with learning disabilities, macrocephaly, dysmorphic features, skeletal anomalies and subependymal heterotopic nodules due to a compound heterozygous mutation of the KIAA1033/WASHC4 gene (p.[Gln442*] and p.[Asp1048Gly]). In this study, we precisely describe the clinical phenotype of the two siblings and provide additional information (histological and proteomic data) derived from the muscle biopsy of the elder sibling to confirm the pathogenicity of the reported variant and establish the function of WASHC4 as relevant for muscle homeostasis. Which, as far as the authors know, has not yet been described in literature.

Project description:We analyzed the functional role of DOR (Diabetes and Obesity Regulated gene) (also named Tp53inp2) in skeletal muscle. We show that DOR has a direct impact on skeletal muscle mass in vivo. Thus, using different transgenic mouse models, we demonstrate that while muscle-specific DOR gain-of-function results in reduced muscle mass, loss-of-function causes muscle hypertrophy. DOR has been described as a protein with two different functions, i.e., a nuclear coactivator and an autophagy regulator (Baumgartner et. al., PLoS One, 2007; Francis et. al., Curr Biol, 2010; Mauvezin et. al., EMBO Rep, 2010; Nowak et. al., Mol Biol Cell, 2009). This is why we decided to analyze which of these two functions could explain the phenotype observed in our mice models. In this regard, we performed a transcriptomic analysis using microarrays looking for genes differentially expressed in the quadriceps muscle of WT and SKM-Tg mice as well as in C and SKM-KO animals. Surprisingly, only a reduced number of genes were dysregulated upon DOR manipulation and most of the genes underwent mild changes in expression. These data strongly suggest that DOR does not operate as a nuclear co-factor in mouse skeletal muscle under the conditions subjected to study. In contrast, DOR enhances basal autophagy in skeletal muscle and promotes muscle wasting when autophagy is a contributor to muscle loss. To determine the functional role of DOR in skeletal muscle, we generated transgenic mice (SKM-Tg) overexpressing DOR specifically in skeletal muscle under the Myosin-Light Chain 1 promoter/enhancer. The open reading frame of DOR was introduced in an EcoRI site in the MDAF2 vector, which contains a 1.5 kb fragment of the MLC1 promoter and 0.9 kb fragment of the MLC1/3 gene containing a 3' muscle enhancer element (Rosenthal et. al., PNAS, 1989; Otaegui et. al., FASEB J, 2003). The fragment obtained after the digestion of this construct with BssHII was the one used to generate both transgenic mouse lines. Nontransgenic littermates were used as controls for the transgenic animals (Wt). In addition, a muscle-specific DOR knock-out mouse line (SKM-KO) was also generated by crossing homozygous DOR loxP/loxP mice with a mouse strain expressing Cre recombinase under the control of the Myosin-Light Chain 1 promoter (Bothe et. al., Genesis, 2000). Deletion of exons 3 and 4 driven by Cre recombinase caused the ablation of DOR expression. Non-expressing Cre DOR loxP/loxP littermates were used as controls for knockout animals (C). Four-month-old male mice were used in all experiments. Mice were in a C57BL/6J pure genetic background.

Project description:We analyzed the functional role of DOR (Diabetes and Obesity Regulated gene) (also named Tp53inp2) in skeletal muscle. We show that DOR has a direct impact on skeletal muscle mass in vivo. Thus, using different transgenic mouse models, we demonstrate that while muscle-specific DOR gain-of-function results in reduced muscle mass, loss-of-function causes muscle hypertrophy. DOR has been described as a protein with two different functions, i.e., a nuclear coactivator and an autophagy regulator (Baumgartner et. al., PLoS One, 2007; Francis et. al., Curr Biol, 2010; Mauvezin et. al., EMBO Rep, 2010; Nowak et. al., Mol Biol Cell, 2009). This is why we decided to analyze which of these two functions could explain the phenotype observed in our mice models. In this regard, we performed a transcriptomic analysis using microarrays looking for genes differentially expressed in the quadriceps muscle of WT and SKM-Tg mice as well as in C and SKM-KO animals. Surprisingly, only a reduced number of genes were dysregulated upon DOR manipulation and most of the genes underwent mild changes in expression. These data strongly suggest that DOR does not operate as a nuclear co-factor in mouse skeletal muscle under the conditions subjected to study. In contrast, DOR enhances basal autophagy in skeletal muscle and promotes muscle wasting when autophagy is a contributor to muscle loss. To determine the functional role of DOR in skeletal muscle, we generated transgenic mice (SKM-Tg) overexpressing DOR specifically in skeletal muscle under the Myosin-Light Chain 1 promoter/enhancer. The open reading frame of DOR was introduced in an EcoRI site in the MDAF2 vector, which contains a 1.5 kb fragment of the MLC1 promoter and 0.9 kb fragment of the MLC1/3 gene containing a 3' muscle enhancer element (Rosenthal et. al., PNAS, 1989; Otaegui et. al., FASEB J, 2003). The fragment obtained after the digestion of this construct with BssHII was the one used to generate both transgenic mouse lines. Nontransgenic littermates were used as controls for the transgenic animals (Wt). In addition, a muscle-specific DOR knock-out mouse line (SKM-KO) was also generated by crossing homozygous DOR loxP/loxP mice with a mouse strain expressing Cre recombinase under the control of the Myosin-Light Chain 1 promoter (Bothe et. al., Genesis, 2000). Deletion of exons 3 and 4 driven by Cre recombinase caused the ablation of DOR expression. Non-expressing Cre DOR loxP/loxP littermates were used as controls for knockout animals (C). Four-month-old male mice were used in all experiments. Mice were in a C57BL/6J pure genetic background. We used microarrays to analyze the effect of DOR gain-of-function and DOR ablation on skeletal muscle gene expression Total RNA from quadriceps muscles from 4-month-old male mice was extracted and used for hibridization on Affimetrix microarrays

			Action	DRS
	20250710_080139_AH_Ozempic_Gastrocnemius_Mouse_non_treated.sne	Other
	20250710_080321_AH_Ozempic_Gastrocnemius_mouse_gelb_immobilisiet.sne	Other
	20250721_125208_AH_Ozempic_untreated_semaglitude_Pairfeeding.sne	Other
	20250721_125403_AH_Ozempic_immobil_Semaglitude_PairFeeding.sne	Other
	AH_Ozempic_Gastrocnemius_Mouse_non_treated_Report_AH_NME_Proteins.tsv	Tabular

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Pharmacological weight loss with incretin-based therapies does not result in a disproportionate loss of muscle mass or function in obese mice and humans

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