dusp22 crispr activation plasmid  (Santa Cruz Biotechnology)

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) DUSP22 expression in aged individuals (over 70 years, n = 15) and aged individuals diagnosed with sarcopenia (over 70 years, n = 18), p = 0.0009 (obtained from the Singapore Sarcopenia Study; (GEO accession no. GSE111016 (Migliavacca et al, )). ( B ) DUSP22 expression in C2C12 murine myotubes treated with vehicle or dexamethasone (Dex) to induce atrophy ( n = 3 each) Custer 1 ( p = 0.024), Cluster 2 ( p = 0.13), Cluster 3 ( p = 0.0246). Expression was measured using RNA Seq. TPM=transcript per million. ( C ) qPCR analysis of DUSP22 expression in four models of muscle atrophy: (1) C2C12 myotubes treated with Dex ( n = 5), p = 7.67E−05, (2) the TA muscle of C57BL/6 mice treated with Dex ( n = 4), p = 0.09, (3) the TA muscle of young (5 months-old, n = 9) and geriatric (27 months-old, n = 8) C57BL/6 mice, p = 0.0324, (4) the TA of C57BL/6 mice after hind limb immobilization ( n = 3), p = 0.018. ( D ) qPCR of DUSP22 expression in C2C12 myoblasts transfected with a DUSP22 CRISPR activation plasmid (DUSP22 endo OE) or control plasmid (CON endo OE) ( n = 3), p = 0.0022. ( E ) Fast myosin (MYH2) immunocytochemistry of CON endo OE and DUSP22 endo OE myoblasts after 96 h culture in DM (scale bar = 100 µm). ( F ) Fusion index ( n = 6). ( G ) Differentiation index ( n = 6), p = 9.91E−09. ( H – L ) qPCR analysis of gene expression related to the following: ( H ) Mitochondrial homeostasis (PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha, p = 1.44E−05), UCP-3 (mitochondrial uncoupling protein 3, p = 4.61E−05), Acly (ATP citrate lyase, p = 0.5141)) ( n = 4). ( I ) Autophagy (LC-3B (microtubule-associated proteins 1 A/1B light chain 3B, p = 0.0152), CtsL (cathepsin L, p = 4.76E−05)) ( n = 4). ( J ) Ubiquitin-proteasome system (UPS) (UBR2 (ubiquitin protein ligase E3, p = 0.0031), Psmd11 (proteasome 26S subunit, non-ATPase 11, p = 0.1718) ( n = 4). ( K ) Myosin heavy chain levels (slow myosin MYH7, p = 7.23E−06, fast myosin MYH1, p = 0.0171) ( n = 4), and ( L ) FoxO3a-related signaling (FoxO3a ( p = 0.0004), MurF-1 ( p = 0.0019), atrogin-1 ( p = 0.001), p62 ( p = 8.67E−08), TGIF (TGFB induced factor homeobox 1, p = 0.0001), ATF4 (activating transcription factor 4, p = 0.3974), Bnip3 (BCL2/adenovirus E1B 19 kDa protein-interacting protein 3, p = 0.0887); Gadd45a (growth arrest and DNA damage inducible alpha, p = 4.19E−06), SMART (specific of muscle atrophy and regulated by transcription, p = 0.0006), MUSA1 (muscle ubiquitin ligase of SCF complex in atrophy-1, p = 0.2357)) ( n = 4). Box plots represent the distribution of DUSP22 expression levels. The center line indicates the median (50th percentile, Q2), representing the middle value of the dataset. The box bounds correspond to the interquartile range (IQR), extending from the 25th percentile (Q1, lower bound) to the 75th percentile (Q3, upper bound). Whiskers extend to the smallest and largest values within 1.5 × IQR from Q1 and Q3, representing the minimum (lower whisker) and maximum (upper whisker) values within this range. Data points that fall beyond this range are considered outliers and are displayed as individual points outside the whiskers. * p < 0.05, ** p < 0.01, *** p < 0.001, and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Expressing, RNA Sequencing, Transfection, CRISPR, Activation Assay, Plasmid Preparation, Control, Immunocytochemistry, Gene Expression, Ubiquitin Proteomics, Whisker Assay

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A , B ) Expression array profiling of DUSP22, MuRF-1, atrogin-1, and UBR2 expression levels (VST) in a database obtained from muscle biopsies, analyzed using Correlation AnalyzeR. ( C ) qPCR analysis of DUSP22 ( p = 7.22E−09), UBR2 ( p = 0.25), MuRF-1 ( p = 0.0101), atrogin-1 ( p = 0.0005) expression in C2C12 myotubes cultured treated with DM and control siRNA or DUSP22 siRNA for 48 h ( n = 5). ( D ) Fast myosin (MYH2) immunocytochemistry of C2C12 myoblasts cultured as follows: (1) 120 h incubation with DM; (2) 72 h incubation with DM and 48 h incubation with DM plus control, DUSP22 siRNA; (3) Following 72 h incubation with DM, 24 h incubation in with DM plus control, scrambled siRNA and additional 24 h treatment with 10 μM Dex plus siRNA; (4) Following 72 h incubation with DM, 24 h incubation in with DM plus DUSP22 siRNA and additional 24 h treatment with 10 μM Dex plus siRNA (scale bar = 100 μm). ( E ) Myotube diameter ( n = 4, p = siCON (3.01E−05), siDUSP22+Dex (0.0003)). ( F ) Myotube distribution. ( G ) Differentiation index of C2C12 myoblasts treated as in part ( D ) ( n = 4, p = siCON (0.0068), siDUSP22+Dex (0.0037))). ( H ) Fusion index ( n = 4). * p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Expressing, Cell Culture, Control, Immunocytochemistry, Incubation

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Western blot analysis of FoxO3a and Akt phosphorylation in C2C12 myotubes treated with control or DUSP22 siRNA in the presence or absence of Dex. ( B ) Quantification of FOXO3a phosphorylation, which is inversely proportional to activity ( n = 6, p-FOXO3A/FOXO3A p =siDUSP22 (7.8E−05), siCON (0.0002), siDUSP22+Dex (0.018), FOXO3A p = siDUSP22 (3.37E−05), siCON (0.0024), siDUSP22+Dex (0.0013)). ( C ) Quantification of Akt phosphorylation, which is directly proportional to activity ( n = 6, p-AKT/AKT p = siDUSP22 (7.8E−05), siCON (0.0002), siDUSP22+Dex (0.018)). ( D ) qPCR analysis of atrogin-1 ( p = siDUSP22 (0.0187), siCON (0.0002), siDUSP22+Dex (0.0451)), MuRF-1 ( p = siDUSP22 (0.0037), siCON (0.0001), siDUSP22+Dex (0.0044)), and DUSP22 ( p =siDUSP22 (1.8E−05), siCON (0.0067), siDUSP22+Dex (2.91E−05)) expression ( n = 6,3). ( E ) Western blot of atrogin-1 and MuRF-1 expression levels. ( F ) Quantification of atrogin-1 ( p = siDUSP22 (0.0125), siCON (0.5.05E−09), siDUSP22+Dex (0.0003)), MuRF-1 ( p = siDUSP22 (0.0226), siCON (0.0033), siDUSP22+Dex (0.0098)), and DUSP22 ( p = siDUSP22 (0.0023), siCON (0.0356), siDUSP22+Dex (0.0353)) levels ( n = 5). ( G ) Fast-type myosin immunostaining of C2C12 myoblasts after culture in DM for 24 h and treatment with control, scrambled siRNA or DUSP22 siRNA for 72 h. Quantification of the fast-type myosin positive myotubes is also shown ( n = 5, p = 0.0001). ( H ) qPCR analysis of DUSP22 ( p = 0.0065), myosin heavy chains (slow myosin MYH7 ( p = 0.0004), fast myosin MYH2 ( p = 0.0024), fast myosin MYH1 ( p = 0.002), and fast myosin MYH4 ( p = 0.0002)), myogenin (MyoG) ( p = 0.0005) and FOXO3a ( p = 0.0171) expression ( n = 3). ( I ) Western blot analysis of MYH2 ( p = 0.015), p-JNK ( p = 0.0316), c-jun ( p = 0.0086), c-jun phosphorylation ( p = 0.0031), atrogin-1 ( p = 0.0333), MuRF-1 ( p = 0.0021), and DUSP22 ( p = 0.0026) (n = 3). ( J ) Quantification of expression and phosphorylation levels. * p < 0.05, ** p < 0.01, *** p < 0.001, and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Western Blot, Phospho-proteomics, Control, Activity Assay, Expressing, Immunostaining

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Chemical structure of BML-260 and CB-Dock2 modeling of BML-260 binding to the active site of human DUSP22 (Pocket C5 and score -5.8. Chain A: GLY-1, PRO0, ASP57, CYS88, LEU89, ALA90, GLY91, VAL92, SER93, ARG94, SER123, CYS124, ALA125, ASN126, ASN128). ( B ) Fast myosin (MYH2) immunostaning of C2C12 myoblasts cultured as follows: (1) DM for 120 h (untreated); (2) DM for 96 h and DM plus 10 μM Dex for 24 h; (3) DM for 96 h and DM plus 10 μM Dex and 12.5 μM BML-260 for 24 h (scale bar = 100 μm). ( C ) Mean myotube diameter ( n = 4, p = (Vehicle = 0.0038), (BML-260 = 0.0051)). ( D ) Myotube diameter distribution. ( E ) Fusion index ( n = 3). ( F ) Differentiation index ( n = 3, p = (Vehicle = 0.0731), (BML-260 = 0.0282)). ( G ) SUnSET assay of protein synthesis rate measuring puromycin incorporation ( n = 3). ( H ) Quantification of the SUnSET assay ( p = (Vehicle = 0.0747), (BML-260 = 0.0401)). ( I ) qPCR analysis of atrogin-1 ( p = (Vehicle = 7.65E−07), (BML-260 = 0.0194)) and MuRF-1( p = (Vehicle = 7.01E−06), (BML-260 = 0.112)) expression ( n = 12). ( J ) Western blot analysis of atrogin-1, MuRF-1, and DUSP22. ( K – M ) Quantification of atrogin-1 ( p = Vehicle (3.74E−09), Dex+BML-260 (0.0016)), MuRF-1 ( p = Vehicle (0.0002), Dex+BML-260 (0.0025)) ( n = 6) and DUSP22 ( p = Vehicle (0.0029), Dex+BML-260 (0.0737)) ( n = 3). *= p < 0.05, **= p < 0.01, and ****= p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Binding Assay, Cell Culture, Expressing, Western Blot

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Schematic of the experimental protocol. ( B ) Western blot analysis of DUSP22 in the Dex-treated tibialis anterior (TA) muscle 3 d after delivery of control or DUSP22 siRNA ( n = 3). ( C ) Quantification of DUSP22 expression ( n = 3, p = 0.0308). ( D ) TA muscle mass ( n = 4, p = (siCON = 0.006, siDUSP22+Dex = 0.0042)). ( E ) Representative H&E staining, and myosin heavy chain IIa (MYHIIa; type 2 A) and IIb (MYHIIb; type 2B) immunostaining of the TA muscle. ( F ) TA myofiber CSA ( n = 4, p = ((siCON = 1.34E−30, siDUSP22+Dex = 1.31E−22)). At least 80 fibers were measured for each sample ( G ) TA myofiber area distribution. ( H ) Type 2A myofiber distribution. ( I ) Type 2B myofiber distribution. ( J ) Western blot analysis of phosphorylated FOXO3a (p-FOXO3a), FOXO3a, phosphorylated c-jun (p-c-jun), c-jun, phosphorylated JNK (p-JNK), JNK in the TA muscle ( n = 4). ( K ) Quantification of p-FOXO3a ( p = ((siCON = 0.0958, siDUSP22+Dex = 0.0255)), FOXO3a ( p = ((siCON = 0.0068, siDUSP22+Dex = 0.0.001)), P-JNK ( p = ((siCON = 0.1087, siDUSP22+Dex = 0.1271)), and JNK ( p = ((siCON = 1.61E−05, siDUSP22+Dex = 0.0004)). ( L ) Quantification of P-c-jun ( p = ((siCON = 0.5016, siDUSP22+Dex = 0.0017)) and c-jun ( p = ((siCON = 6.27E−06, siDUSP22+Dex = 3.52E−06)). GAPDH was used for the normalization of FOXO3a, p-JNK, JNK, p-c-Jun and c-Jun expression. FOXO3a was used for the normalization of p-FOXO3a expression. ( M ) Western blot analysis of p62 ( p = ((siCON = 0.0297, siDUSP22+Dex = 0.0042)) and MuRF-1 ( p = ((siCON = 0.1484, siDUSP22+Dex = 0.0245)) ( n = 4). GAPDH was used for normalization of expression. ( N ) Quantification of p62 and MuRF-1. * p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Western Blot, Control, Expressing, Staining, Immunostaining

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A , B ) Western blot and densitometry analysis of AKT phosphorylation in the Dex-treated tibialis anterior (TA) muscle 3 d after delivery of control or DUSP22 siRNA ( n = 4) ( p = (siCON = 0.029, siDUSP22+Dex = 0.0412)). GAPDH was used for normalization of expression. * p < 0.05 indicate significantly increased or decreased. n represents biological replicates analyzed by Student’s t test. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Western Blot, Phospho-proteomics, Control, Expressing

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Tetanic muscle contraction measurement in the TA muscle of aged ( n = 3) ( p = 0.3974) or middle aged mice ( n = 4) ( p = 0.0807) 3 d after the delivery of control or DUSP22 siRNA. ( B ) Twitch force measure in 15-month-old mice 3 d after the delivery of control or DUSP22 siRNA ( n = 4) ( p = 0.1054, 0.1677, 0.1964, 0.1858, 0.2118, 0.234, 0.2489, 0.2684, 0.2947). n represents biological replicates analyzed by Student’s t test. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Control

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Schematic of the experimental protocol. ( B ) Body weight during 13 d treatment with vehicle, 15 mg/kg Dex, or 15 mg/kg Dex and 5 mg/kg BML-260. ( C ) Grip strength ( n = 4, p = (Vehicle = 0.3426, BML-260 = 0.224). ( D ) Rotarod performance in the constant (RPM) ( p = (Vehicle = 0.05, BML-260 = 0.0263)) and acceleration (latency to fall) ( p = (Vehicle = 0.0003, BML-260 = 0.0132)) models ( n = 4). ( E ) Representative H&E staining of the gastrocnemius muscle. ( F ) Myofiber CSA ( n = 4, p = (Vehicle = 1.98E−84, BML-260 = 2.93E−32)). ( G ) Myofiber area distribution. At least 100 fibers were measured for each sample ( H ) TA muscle mass ( n = 4, p = (Vehicle = 0.0042, BML-260 = 0.0208)). ( I , J ) Western blot analysis of atrogin-1 ( p = (Vehicle = 0.0029, BML-260 = 0.0014)), MuRF-1 ( p = (Vehicle = 0.0086, BML-260 = 0.0498)), and DUSP22 ( p = (Vehicle = 0.0034, BML-260 = 0.0258)) expression in the TA muscle ( n = 3). GAPDH was used for normalization of expression. * p < 0.05, ** p < 0.01, and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Staining, Western Blot, Expressing

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Experimental protocol to knockdown DUSP22 expression in the TA of aged mice. ( B ) Western blot analysis of DUSP22 and MuRF-1 and expression levels ( n = 4). GAPDH was used for normalization of expression. ( C ) Quantification of DUSP22 ( p = (3 M = 0.0004, 27 M+siDUSP22 = 0.0007)) and MuRF-1 ( p = (3 M = 0.0148, 27 M+siDUSP22 = 0.0046)). ( D ) Change in TA muscle mass ( p = 0.1749) over the course of the experiment. ( E ) Representative H&E staining of the TA muscle. ( F ) TA myofiber CSA ( n = 5, p = 7.54E−35). At least 150 fibers were measured for each sample ( G ) Western blot of FOXO3a, atrogin-1, MuRF-1, and DUSP22 levels in the TA muscle from the control siRNA treated left and DUSP22 siRNA treated right leg ( n = 4). ( H ) Change in FOXO3a ( p = 0.1852), atrogin-1 ( p = 0.0532), and MuRF-1 ( p = 0.0052), DUSP22 ( p = 0.1466) expression relative to GAPDH. ( I ) Experimental protocol for DUSP22 pharmacological targeting in aged mice. ( J ) Body weight over the course of the experiment. ( K ) Grip strength ( p = (5 M = 0.0002, Aged+BML-260 = 0.0702) and rotarod performance ( p = 0.0381) in the latency to fall test ( n = 5,4). ( L ) Mass of the quadriceps ( p = (5 M = 0.0002, Aged+BML-260 = 0.0539), gastrocnemius ( p = (5 M = 0.0003, Aged+BML-260 = 0.0383), TA ( p = (5 M = 0.0229, Aged+BML-260 = 0.04919) and soleus ( p = (5 M = 0.1484, Aged+BML-260 = 0.2699) muscles ( n = 5). ( M ) qPCR analysis of MuRF-1( p = 0.0194) and atrogin-1 ( p = 0.0737) expression ( n = 3,4). ( N ) qPCR analysis of myostatin (Mstn) ( p = 0.0072) and PGC-1α ( p = 0.0423) expression ( n = 3,4). ( O ) MYHIIa (type 2a), MYHIIb (type 2b), and MYHIIx (type 2x), DAPI and laminin staining in the TA and gastrocnemius muscles (5 M = 5 months-old). Scale bar = 100 µm. ( P ) CSA of the type 2a ( p = (5 M = 0.0016, Aged+BML-260 = 0.1403), 2b ( p = (5 M = < 0.0001, Aged+BML-260 = 0.0004), and 2x ( p = (5 M = 0.001, Aged+BML-260 = 0.005) myofibers ( n = 4). ( Q ) Minimal Feret’s diameter of the type 2a ( p = (5 M = 0.0057, Aged+BML-260 = 0.0662), 2b ( p = (5 M = < 0.0001, Aged+BML-260 = 0.0017), and 2x ( p = (5 M = 0.0092, Aged+BML-260 = 0.0155) myofibers. * p < 0.05, ** p < 0.01, *** p < 0.001 and **** p < 0.0001 indicate significantly increased or decreased. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Knockdown, Expressing, Western Blot, Staining, Control, Muscles

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Western blot analysis of DUSP22 expression in the TA of aged mice treated with BML-260 ( n = 4,3) ( p = (Young = 0.0362, Aged+BML-260 = 0.0054)). GAPDH was used for normalization of expression. * p < 0.05 and ** p < 0.01 indicate significantly increased or decreased. ( B , C ) Western blot analysis of DUSP22 expression in the TA ( n = 3,5,6) ( p = (Sham = 0.0051, BML-260 = 0.0488)) ( B ) and gastrocnemius muscle ( n = 3,5,6) ( p = (Sham=0.6845, BML-260 = 0.0008)) ( C ) of immobilized (IMM) mice treated with BML-260. For the TA muscle, MYH4 (myosin heavy chain 2B) ( p = (Sham=0.0253, BML-260 = 0.0288)) levels are also shown. GAPDH was used for normalization of expression. * p < 0.05, ** p < 0.01, and *** p < 0.001 indicate significantly increased or decreased. n represents biological replicates analyzed by Student’s t test. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Western Blot, Expressing

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: ( A ) Effect of immobilization on skeletal muscle mass using the plastic EP tube method ( n = 3). ( B ) qPCR analysis of DUSP22 expression in the TA muscle (IM = immobilized) ( n = 3) ( p = 0.018). ( C ) Plot of DUSP22 expression in relation to TA mass ( n = 6). ( D ) Western blot analysis of DUSP22 expression ( n = 3) ( p = 0.1699). ( E ) TA mass ( n = 9,7) ( p = (Sham = <0.0001, BML-260 = 0.007)). ( F ) Western blot analysis of atrogin-1( p = (Sham = 0.0005, BML-260 = 0.0009)), MuRF-1 ( p = (Sham = 0.008, BML-260 = 0.0057)), and DUSP22 ( p = (Sham = 0.0007, BML-260 = 0.054)) levels in the TA muscle ( n = 3). Quantification of atrogin-1, MuRF-1, and DUSP22 levels relative to GAPDH are also shown. ( G ) Micrographs of MYH2-immunostained human myotubes treated as follows: 1) Vehicle alone, 2) 10 μM Dex for 24 h, 3) 10 μM Dex and 12.5 μM BML-260 for 24 h. ( H ) Mean myotube diameter ( n = 5,4) ( p = (Vehicle = 0.0001, BML-260 = 0.033)). ( I ) Micrographs of MYH2-immunostained human myotubes treated as follows: (1) 48 h incubation in with DM plus control, scrambled siRNA; (2) 48 h incubation with DM plus DUSP22 siRNA: (3) 24 h incubation with DM plus control, scrambled siRNA and additional 24 h treatment with 10 μM Dex plus siRNA; (4) 24 h incubation with DM plus DUSP22 siRNA and additional 24 h treatment with 10 μM Dex plus siRNA. ( J ) Myotube diameter ( n = 7,5) ( p = (siCON = 9.79E−06., siDUSP22+Dex = 0.0003)). ( K ) qPCR analysis of DUSP22 expression in the Dex-treated human myotubes ( n = 3) ( p = 0.0129). ( L ) qPCR analysis of MuRF-1( p = (siCON = 0.0286, siDUSP22+Dex = 0.049)) expression in the Dex-treated human myotubes ( n = 3). * p < 0.05, ** p < 0.01, and *** p < 0.001 indicate significantly increased or decreased. ( M ) Working model of the effect of DUSP22 targeting on skeletal muscle atrophy: 1) In healthy muscle, Akt signaling can promote hypertrophy by increasing protein synthesis and inhibiting the activity of FOXO3a. 2) In the context of skeletal muscle wasting, the Akt pathway can become suppressed and FOXO3a signaling is upregulated. The results from this study show that targeting DUSP22 in wasting muscle downregulates JNK and reduces FOXO3a signaling. These events occur independently of Akt signaling activation, which remains suppressed. DUSP22 targeting, via pharmacology or gene knockdown, is sufficient to enhance function, improve histopathology, and lower atrogene expression in multiple forms of skeletal muscle wasting. n represents biological replicates. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Expressing, Western Blot, Incubation, Control, Activity Assay, Activation Assay, Knockdown, Histopathology

Journal: EMBO Molecular Medicine

Article Title: Modulating phosphatase DUSP22 with BML-260 ameliorates skeletal muscle wasting via Akt independent JNK-FOXO3a repression

doi: 10.1038/s44321-025-00234-2

Figure Lengend Snippet: Western blot analysis of DUSP22 ( p = (Sham = 0.0341, BML-260 = 0.0494)), JNK and phosphorylated JNK (JNK-P) ( p = (Sham = 0.0052, BML-260 = 0.0007)) levels in the TA muscle of immobilized mice ( n = 3,4). GAPDH was used for normalization of expression. * p < 0.05, ** p < 0.01, and *** p < 0.001 indicate significantly increased or decreased. n represents biological replicates analyzed by Student’s t test. Error bars represent the standard error of the mean (SEM). .

Article Snippet: DUSP22 CRISPR Activation Plasmid (m) , Santa Cruz , sc-430587-ACT.

Techniques: Western Blot, Expressing