Key Specifications Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|H, M, R||IP, WB||Rb||Purified||Polyclonal Antibody|
|Presentation||Protein A Purified immunoglobulin in 30% glycerol, 0.07M Tris-glycine, pH 7.4, 0.105 M NaCl, 0.035% sodium azide as a preservative.|
|Application||This Anti-Akt2/PKBβ Antibody is validated for use in IP, WB for the detection of Akt2/PKBβ.|
|Safety Information according to GHS|
|Material Size||200 µg|
|Anti-Akt2/PKB#946; (rabbit polyclonal IgG) - 2123173||2123173|
|Anti-Akt2/PKB#946; (rabbit polyclonal IgG) - 2145426||2145426|
|Anti-Akt2/PKB#946; (rabbit polyclonal IgG) - NG1830454||NG1830454|
|Anti-Akt2/PKBb (rabbit polyclonal IgG) - 2316794||2316794|
|Anti-Akt2/PKBb - JBC1873440||JBC1873440|
|Anti-Akt2/PKBbeta; - 22444||22444|
|Anti-Akt2/PKBbeta; - 27551||27551|
|Anti-Akt2/PKBβ (rabbit polyclonal IgG) -2504292||2504292|
|Anti-Akt2/PKBβ - 2542051||2542051|
|Reference overview||Application||Pub Med ID|
|Dose-dependent effects of sirolimus on mTOR signaling and polycystic kidney disease.|
Novalic, Z; van der Wal, AM; Leonhard, WN; Koehl, G; Breuning, MH; Geissler, EK; de Heer, E; Peters, DJ
Journal of the American Society of Nephrology : JASN 23 842-53 2012
Inhibition of the mammalian target of rapamycin (mTOR) shows beneficial effects in animal models of polycystic kidney disease (PKD); however, two clinical trials in patients with autosomal dominant PKD failed to demonstrate a short-term benefit in either the early or progressive stages of disease. The stage of disease during treatment and the dose of mTOR inhibitors may account for these differing results. Here, we studied the effects of a conventional low dose and a higher dose of sirolimus (blood levels of 3 ng/ml and 30-60 ng/ml, respectively) on mTOR activity and renal cystic disease in two Pkd1-mutant mouse models at different stages of the disease. When initiated at early but not late stages of disease, high-dose treatment strongly reduced mTOR signaling in renal tissues, inhibited cystogenesis, accelerated cyst regression, and abrogated fibrosis and the infiltration of immune cells. In contrast, low-dose treatment did not significantly reduce renal cystic disease. Levels of p-S6Rp(Ser240/244), which marks mTOR activity, varied between kidneys; severity of the renal cystic phenotype correlated with the level of mTOR activity. Taken together, these data suggest that long-term treatment with conventional doses of sirolimus is insufficient to inhibit mTOR activity in renal cystic tissue. Mechanisms to increase bioavailability or to target mTOR inhibitors more specifically to kidneys, alone or in combination with other compounds, may improve the potential for these therapies in PKD.
|The Akt isoforms are present at distinct subcellular locations.|
Santi, SA; Lee, H
American journal of physiology. Cell physiology 298 C580-91 2010
Akt is involved in the regulation of diverse cellular functions such as cell proliferation, energy metabolism, and apoptosis. Although three Akt isoforms are known, the function of each isoform is poorly understood. To gain a better understanding of each Akt isoform, we examined the subcellular localization and expression of each isoform in transformed and nontransformed cells. Akt1 was localized in the cytoplasm, which is in agreement with the currently accepted model that cytoplasmic Akt is translocated and activated at the inner leaflet of the plasma membrane. Interestingly, HEK-293 and HEK-293T cells contained Akt1 in the nucleus and cytoplasm, respectively, suggesting that SV40 T-antigen plays a crucial role in the cytoplasmic localization and activation of Akt1 in HEK-293T. Akt2 was colocalized with the mitochondria, while Akt3 was localized in both the nucleus and nuclear membrane. The subcellular localization of the Akt isoforms was not substantially altered in response to ionizing radiation or EGF. Furthermore, the ablation of one Akt isoform by small interfering RNA (siRNA) did not alter the subcellular location of the remaining isoforms, suggesting that the major function of one isoform is not compensated for by other isoforms. Together, our data support the notion that Akt2 and Akt3 are regulated at the mitochondrial and nuclear membranes, respectively. The mitochondrial localization of Akt2 raises the possibility that this isoform may be involved in both glucose-based energy metabolism and suppression of apoptosis, two Akt functions previously identified with anti-pan-Akt antibodies.
|Phosphorylation of PRAS40 on Thr246 by PKB/AKT facilitates efficient phosphorylation of Ser183 by mTORC1.|
Nascimento EB, Snel M, Guigas B, van der Zon GC, Kriek J, Maassen JA, Jazet IM, Diamant M, Ouwens DM
Cell Signal 22 961-7. Epub 2010 Feb 6. 2010
Type 2 diabetes is associated with alterations in protein kinase B (PKB/Akt) and mammalian target of rapamycin complex 1 (mTORC1) signalling. The proline-rich Akt substrate of 40-kDa (PRAS40) is a component of mTORC1, which has a regulatory function at the intersection of the PKB/Akt and mTORC1 signalling pathway. Phosphorylation of PRAS40-Thr246 by PKB/Akt, and PRAS40-Ser183 and PRAS40-Ser221 by mTORC1 results in dissociation from mTORC1, and its binding to 14-3-3 proteins. Although all phosphorylation sites within PRAS40 have been implicated in 14-3-3 binding, substitution of Thr246 by Ala alone is sufficient to abolish 14-3-3 binding under conditions of intact mTORC1 signalling. This suggests that phosphorylation of PRAS40-Thr246 may facilitate efficient phosphorylation of PRAS40 on its mTORC1-dependent sites. In the present study, we investigated the mechanism of PRAS40-Ser183 phosphorylation in response to insulin. Insulin promoted PRAS40-Ser183 phosphorylation after a euglycaemic-hyperinsulinaemic clamp in human skeletal muscle. The insulin-induced PRAS40-Ser183 phosphorylation was further evidenced in vivo in rat skeletal and cardiac muscle, and in vitro in A14 fibroblasts, 3T3L1 adipocytes and L6 myotubes. Inhibition of mTORC1 by rapamycin or amino acid deprivation partially abrogated insulin-mediated PRAS40-Ser183 phosphorylation in cultured cell lines. However, lowering insulin-induced PRAS40-Thr246 phosphorylation using wortmannin or palmitate in cell lines, or by feeding rats a high-fat diet, completely abolished insulin-mediated PRAS40-Ser183 phosphorylation. In addition, replacement of Thr246 by Ala reduced insulin-mediated PRAS40-Ser183 phosphorylation. We conclude that PRAS40-Ser183 is a component of insulin action, and that efficient phosphorylation of PRAS40-Ser183 by mTORC1 requires the phosphorylation of PRAS40-Thr246 by PKB/Akt.
|Effects of endurance exercise training on insulin signaling in human skeletal muscle: interactions at the level of phosphatidylinositol 3-kinase, Akt, and AS160.|
Frøsig, C; Rose, AJ; Treebak, JT; Kiens, B; Richter, EA; Wojtaszewski, JF
Diabetes 56 2093-102 2007
The purpose of this study was to investigate the mechanisms explaining improved insulin-stimulated glucose uptake after exercise training in human skeletal muscle. Eight healthy men performed 3 weeks of one-legged knee extensor endurance exercise training. Fifteen hours after the last exercise bout, insulin-stimulated glucose uptake was approximately 60% higher (P less than 0.01) in the trained compared with the untrained leg during a hyperinsulinemic-euglycemic clamp. Muscle biopsies were obtained before and after training as well as after 10 and 120 min of insulin stimulation in both legs. Protein content of Akt1/2 (55 +/- 17%, P less than 0.05), AS160 (25 +/- 8%, P = 0.08), GLUT4 (52 +/- 19%, P less than 0.001), hexokinase 2 (HK2) (197 +/- 40%, P less than 0.001), and insulin-responsive aminopeptidase (65 +/- 15%, P less than 0.001) increased in muscle in response to training. During hyperinsulinemia, activities of insulin receptor substrate-1 (IRS-1)-associated phosphatidylinositol 3-kinase (PI3-K) (P less than 0.005), Akt1 (P less than 0.05), Akt2 (P less than 0.005), and glycogen synthase (GS) (percent I-form, P less than 0.05) increased similarly in both trained and untrained muscle, consistent with increased phosphorylation of Akt Thr(308), Akt Ser(473), AS160, glycogen synthase kinase (GSK)-3alpha Ser(21), and GSK-3beta Ser(9) and decreased phosphorylation of GS site 3a+b (all P less than 0.005). Interestingly, training improved insulin action on thigh blood flow, and, furthermore, in both basal and insulin-stimulated muscle tissue, activities of Akt1 and GS and phosphorylation of AS160 increased with training (all P less than 0.05). In contrast, training reduced IRS-1-associated PI3-K activity (P less than 0.05) in both basal and insulin-stimulated muscle tissue. Our findings do not support generally improved insulin signaling after endurance training; rather it seems that improved insulin-stimulated glucose uptake may result from hemodynamic adaptations as well as increased cellular protein content of individual insulin signaling components and molecules involved in glucose transport and metabolism.
|Exercise reverses high-fat diet-induced impairments on compartmentalization and activation of components of the insulin-signaling cascade in skeletal muscle.|
Yaspelkis, BB; Lessard, SJ; Reeder, DW; Limon, JJ; Saito, M; Rivas, DA; Kvasha, I; Hawley, JA
American journal of physiology. Endocrinology and metabolism 293 E941-9 2007
The aims of this investigation were 1) to determine whether endurance exercise training could reverse impairments in insulin-stimulated compartmentalization and/or activation of aPKCzeta/lambda and Akt2 in skeletal muscle from high-fat-fed rodents and 2) to assess whether the PPARgamma agonist rosiglitazone could reverse impairments in skeletal muscle insulin signaling typically observed after high-fat feeding. Sprague-Dawley rats were placed on chow (NORCON, n = 16) or high-fat (n = 64) diets for 4 wk. During a subsequent 4-wk experimental period, high-fat-fed rats were allocated (n = 16/group) to either sedentary control (HFC), exercise training (HFX), rosiglitazone treatment (HFRSG), or a combination of both exercise training and rosiglitazone (HFRX). Following the 4-wk experimental period, animals underwent hindlimb perfusions. Insulin-stimulated plasma membrane-associated aPKCzeta and -lambda protein concentration, aPKCzeta/lambda activity, GLUT4 protein concentration, cytosolic Akt2, and aPKCzeta/lambda activities were reduced (P less than 0.05) in HFC compared with NORCON. Cytosolic Akt2, aPKCzeta, and aPKClambda protein concentrations were not affected in HFC compared with NORCON. Exercise training reversed the deleterious effects of the high-fat diet such that insulin-stimulated compartmentalization and activation of components of the insulin-signaling cascade in HFX were normalized to NORCON. High-fat diet-induced impairments to skeletal muscle glucose metabolism were not reversed by rosiglitazone administration, nor did rosiglitazone augment the effect of exercise. Our findings indicate that chronic exercise training, but not rosiglitazone, reverses high-fat diet induced impairments in compartmentalization and activation of components of the insulin-signaling cascade in skeletal muscle.
|Use of RNA interference-mediated gene silencing and adenoviral overexpression to elucidate the roles of AKT/protein kinase B isoforms in insulin actions|
Katome, T., et al
J Biol Chem, 278:28312-23 (2003) 2003