Other
13 Authors
- Xie B,
- Sakamoto K,
- Wang HY,
- Zhu S,
- Rong P,
- MacKintosh C,
- Chen Q,
- Quan C,
- Sheng Y,
- Chen L,
- Li M,
- Ducommun S,
- Chen S
First Author | Chen Q | Year | 2017 |
Journal | Diabetologia | Volume | 60 |
Issue | 2 | Pages | 336-345 |
PubMed ID | 27826658 | Mgi Jnum | J:238728 |
Mgi Id | MGI:5823519 | Doi | 10.1007/s00125-016-4151-9 |
Citation | Chen Q, et al. (2017) A Tbc1d1 Ser231Ala-knockin mutation partially impairs AICAR- but not exercise-induced muscle glucose uptake in mice. Diabetologia 60(2):336-345 |
abstractText | AIMS/HYPOTHESIS: TBC1D1 (tre-2/USP6, BUB2, cdc16 domain family member 1) is a Rab GTPase-activating protein (RabGAP) that has been implicated in regulating GLUT4 trafficking. TBC1D1 can be phosphorylated by the AMP-activated protein kinase (AMPK) on Ser231, which consequently interacts with 14-3-3 proteins. Given the key role for AMPK in regulating insulin-independent muscle glucose uptake, we hypothesised that TBC1D1-Ser231 phosphorylation and/or 14-3-3 binding may mediate AMPK-governed glucose homeostasis. METHODS: Whole-body glucose homeostasis and muscle glucose uptake were assayed in mice bearing a Tbc1d1 Ser231Ala-knockin mutation or harbouring skeletal muscle-specific Ampkalpha1/alpha2 (also known as Prkaa1/2) double-knockout mutations in response to an AMPK-activating agent, 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR). Exercise-induced muscle glucose uptake and exercise capacity were also determined in the Tbc1d1 Ser231Ala-knockin mice. RESULTS: Skeletal muscle-specific deletion of Ampkalpha1/a2 in mice prevented AICAR-induced hypoglycaemia and muscle glucose uptake. The Tbc1d1 Ser231Ala-knockin mutation also attenuated the glucose-lowering effect of AICAR in mice. Glucose uptake and cell surface GLUT4 content were significantly lower in muscle isolated from the Tbc1d1 Ser231Ala-knockin mice upon stimulation with a submaximal dose of AICAR. However, this Tbc1d1 Ser231Ala-knockin mutation neither impaired exercise-induced muscle glucose uptake nor affected exercise capacity in mice. CONCLUSIONS/INTERPRETATION: TBC1D1-Ser231 phosphorylation and/or 14-3-3 binding partially mediates AMPK-governed glucose homeostasis and muscle glucose uptake in a context-dependent manner. |