Variation in the Ovine Glycogen Synthase Kinase 3 Beta-Interaction Protein Gene (GSKIP) Affects Carcass and Growth Traits in Romney Sheep

The glycogen synthase kinase 3 beta (GSK3β)-interacting protein (encoded by the gene GSKIP) is a small A-kinase anchoring protein, which complexes with GSK3βand protein kinase A (PKA) and acts synergistically with cAMP/PKA signaling to inhibit GSK3β activity. The protein plays a role in regulating glycogen metabolism, protein synthesis, the cell cycle, and in regulating gene expression. In this study, PCR-single strand conformation polymorphism (PCR-SSCP) analyses were used to screen for variation in exon 1 and exon 2 of GSKIP in 840 New Zealand (NZ) Romney sheep. Two SSCP banding patterns representing two different nucleotide variants (A and B) were detected in an exon 1 region, whereas in an exon 2 region only one pattern was detected. Variants A and B of exon 1 had one non-synonymous nucleotide difference c.37A/G (p.Met13Val). The birthweight of sheep of genotype AA (5.9 ± 0.06 kg) was different (p = 0.023) to sheep of genotype AB (5.7 ± 0.06 kg) and BB (5.7 ± 0.06 kg). The hot carcass weight (HCW) of sheep of genotype AA (17.2 ± 0.22 kg) was different (p = 0.012) to sheep of genotype AB (17.6 ± 0.22 kg) and BB (18.0 ± 0.29 kg), and the fat depth at the 12th rib (V-GR) of sheep of genotype AA (7.7 ± 0.31 mm) was different (p = 0.016) to sheep of genotype AB (8.3 ± 0.30 mm) and BB (8.5 ± 0.39 mm). The results suggest that the c.37A/G substitution in ovine GSKIP may affect sheep growth and carcass traits.

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Glycogen Synthase Kinase-3 is involved in glycogen metabolism control and embryogenesis of Rhodnius prolixus

Parasitology ◽

10.1017/s0031182016001487 ◽

2016 ◽

Vol 143 (12) ◽

pp. 1569-1579 ◽

Cited By ~ 6

Author(s):

FLÁVIA B. MURY ◽

MAGDA D. LUGON ◽

RODRIGO NUNES DA FONSECA ◽

JOSE R. SILVA ◽

MATEUS BERNI ◽

...

Keyword(s):

Catalytic Domain ◽

Glycogen Synthase ◽

Classical Model ◽

Glycogen Metabolism ◽

Rhodnius Prolixus ◽

Glycogen Synthase Kinase ◽

Glycogen Synthase Kinase 3 ◽

Adult Survival ◽

Trypanosoma Rangeli ◽

Egg Hatching

SUMMARYRhodnius prolixus is a blood-feeding insect that transmits Trypanosoma cruzi and Trypanosoma rangeli to vertebrate hosts. Rhodnius prolixus is also a classical model in insect physiology, and the recent availability of R. prolixus genome has opened new avenues on triatomine research. Glycogen synthase kinase 3 (GSK-3) is classically described as a key enzyme involved in glycogen metabolism, also acting as a downstream component of the Wnt pathway during embryogenesis. GSK-3 has been shown to be highly conserved among several organisms, mainly in the catalytic domain region. Meanwhile, the role of GSK-3 during R. prolixus embryogenesis or glycogen metabolism has not been investigated. Here we show that chemical inhibition of GSK-3 by alsterpaullone, an ATP-competitive inhibitor of GSK3, does not affect adult survival rate, though it alters oviposition and egg hatching. Specific GSK-3 gene silencing by dsRNA injection in adult females showed a similar phenotype. Furthermore, bright field and 4’−6-diamidino-2-phenylindole (DAPI) staining analysis revealed that ovaries and eggs from dsGSK-3 injected females exhibited specific morphological defects. We also demonstrate that glycogen content was inversely related to activity and transcription levels of GSK-3 during embryogenesis. Lastly, after GSK-3 knockdown, we observed changes in the expression of the Wingless (Wnt) downstream target β-catenin as well as in members of other pathways such as the receptor Notch. Taken together, our results show that GSK-3 regulation is essential for R. prolixus oogenesis and embryogenesis.

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Functional Studies of Shaggy/Glycogen Synthase Kinase 3 Phosphorylation Sites in Drosophila melanogaster

Molecular and Cellular Biology ◽

10.1128/mcb.24.11.4909-4919.2004 ◽

2004 ◽

Vol 24 (11) ◽

pp. 4909-4919 ◽

Cited By ~ 39

Author(s):

Deppie Papadopoulou ◽

Michele Wolfe Bianchi ◽

Marc Bourouis

Keyword(s):

Drosophila Melanogaster ◽

Specific Activity ◽

Glycogen Synthase ◽

Glycogen Metabolism ◽

Glycogen Synthase Kinase ◽

Abnormal Development ◽

Glycogen Synthase Kinase 3 ◽

Signaling Systems ◽

Functional Studies

ABSTRACT Early studies of glycogen synthase kinase 3 (GSK-3) in mammalian systems focused on its pivotal role in glycogen metabolism and insulin-mediated signaling. It is now recognized that GSK-3 is central to a number of diverse signaling systems. Here, we show that the major form of the kinase Shaggy (Sgg), the GSK-3 fly ortholog, is negatively regulated during insulin-like/phosphatidylinositol 3-kinase (PI3K) signaling in vivo. Since genetic studies of Drosophila melanogaster had previously shown that Wingless (Wg) signaling also acts to antagonize Sgg, we investigate how the kinase might integrate, or else discriminate, signaling inputs by Wg and insulin. Using Drosophila cell line assays, we found, in contrast to previous reports, that Wg induces accumulation of its transducer Armadillo (Arm)/β-catenin without significant alteration of global Sgg-specific activity. In agreement with a previous study using human GSK-3β, Wg did not cause phosphorylation changes of the Ser9 or Tyr214 regulatory phosphorylated sites of Sgg. Conversely, as shown in mammalian systems, insulin-induced inhibition of Sgg-specific activity by phosphorylation at the N-terminal pseudosubstrate site (Ser9) did not induce Arm/β-catenin accumulation, showing selectivity in response to the different signaling pathways. Interestingly, a minigene bearing a Ser9-to-Ala change rescued mutant sgg without causing abnormal development, suggesting that the regulation of Sgg via the inhibitory pseudosubstrate domain is dispensable for many aspects of its function. Our studies of Drosophila show that Wg and insulin or PI3K pathways do not converge on Sgg but that they exhibit cross-regulatory interactions.

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