PMID- 19164446
OWN - NLM
STAT- MEDLINE
DCOM- 20090526
LR  - 20211020
IS  - 0888-8809 (Print)
IS  - 1944-9917 (Electronic)
IS  - 0888-8809 (Linking)
VI  - 23
IP  - 4
DP  - 2009 Apr
TI  - Interruption of growth hormone signaling via SHC and ERK in 3T3-F442A 
      preadipocytes upon knockdown of insulin receptor substrate-1.
PG  - 486-96
LID - 10.1210/me.2008-0407 [doi]
AB  - Insulin receptor substrate-1 (IRS-1) is a docking protein tyrosine phosphorylated 
      in response to insulin, IGF-1, GH, and other cytokines. IRS-1 has an N-terminal 
      plekstrin homology domain (which facilitates membrane localization), a 
      phosphotyrosine-binding domain [which associates with tyrosine-phosphorylated 
      insulin receptor or IGF-1 receptor (IGF-1R)], and tyrosine residues that, when 
      phosphorylated, bind signaling molecules. The role of IRS-1 in GH signaling is 
      uncertain. We previously reported that IRS-1 and Janus kinase 2 associate 
      independently of tyrosine phosphorylation via IRS-1's N terminus and that IRS-1 
      reconstitution greatly enhances GH-induced ERK, but not STAT5, activation. We now 
      use GH-responsive 3T3-F442A preadipocytes to study the influence of IRS-1 on GH 
      action. We stably transfected cells with vector only (Control) or a vector 
      encoding IRS-1 short hairpin RNA [knockdown (KD)] and compared representative 
      clones. Immunoblotting confirmed more than 80% knockdown of IRS-1 in KD cells. GH 
      caused characteristic Janus kinase 2 and STAT5 activation in both Control and KD 
      cells, but ERK activation was dramatically reduced in KD cells in GH time course 
      and dose-response experiments. Notably, GH-induced Src homology collagen (SHC) 
      activation and SHC-Grb2 association in KD cells were also markedly diminished 
      compared with Control cells. Subcellular fractionation revealed that IRS-1 in 
      Control cells was largely cytosolic, but the component isolated with plasma 
      membranes was highly enriched in lipid raft membranes (LR). In KD cells, 
      GH-induced ERK activation in the LR fraction was particularly diminished compared 
      with Control cells. These data suggest that LR-enriched IRS-1 contributes 
      substantially to GH-induced ERK activation in LR in 3T3-F442A fibroblasts. 
      Furthermore, our results are consistent with IRS-1 residing upstream of SHC in 
      the GH-induced ERK-signaling pathway.
FAU - Wang, Xiangdong
AU  - Wang X
AD  - University of Alabama at Birmingham, Birmingham, Alabama 35294-0012, USA.
FAU - Yang, Ning
AU  - Yang N
FAU - Deng, Luqin
AU  - Deng L
FAU - Li, Xin
AU  - Li X
FAU - Jiang, Jing
AU  - Jiang J
FAU - Gan, Yujun
AU  - Gan Y
FAU - Frank, Stuart J
AU  - Frank SJ
LA  - eng
GR  - R01 DK058259/DK/NIDDK NIH HHS/United States
GR  - R56 DK058259/DK/NIDDK NIH HHS/United States
GR  - DK58259/DK/NIDDK NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
DEP - 20090122
PL  - United States
TA  - Mol Endocrinol
JT  - Molecular endocrinology (Baltimore, Md.)
JID - 8801431
RN  - 0 (Insulin Receptor Substrate Proteins)
RN  - 0 (Receptors, Somatotropin)
RN  - 0 (STAT5 Transcription Factor)
RN  - 0 (Shc Signaling Adaptor Proteins)
RN  - 9002-72-6 (Growth Hormone)
RN  - EC 2.7.10.2 (Janus Kinase 2)
RN  - EC 2.7.11.1 (Proto-Oncogene Proteins c-akt)
RN  - EC 2.7.11.24 (Extracellular Signal-Regulated MAP Kinases)
SB  - IM
MH  - 3T3 Cells
MH  - Adipocytes/cytology/physiology
MH  - Animals
MH  - Enzyme Activation
MH  - Extracellular Signal-Regulated MAP Kinases/genetics/*metabolism
MH  - Gene Knockdown Techniques
MH  - Growth Hormone/*metabolism
MH  - Insulin Receptor Substrate Proteins/genetics/*metabolism
MH  - Janus Kinase 2/genetics/metabolism
MH  - Membrane Microdomains/metabolism
MH  - Mice
MH  - Proto-Oncogene Proteins c-akt/genetics/metabolism
MH  - Receptors, Somatotropin/genetics/metabolism
MH  - STAT5 Transcription Factor/genetics/metabolism
MH  - Shc Signaling Adaptor Proteins/genetics/*metabolism
MH  - Signal Transduction/*physiology
PMC - PMC2667707
EDAT- 2009/01/24 09:00
MHDA- 2009/05/27 09:00
PMCR- 2010/04/01
CRDT- 2009/01/24 09:00
PHST- 2009/01/24 09:00 [entrez]
PHST- 2009/01/24 09:00 [pubmed]
PHST- 2009/05/27 09:00 [medline]
PHST- 2010/04/01 00:00 [pmc-release]
AID - me.2008-0407 [pii]
AID - 4414 [pii]
AID - 10.1210/me.2008-0407 [doi]
PST - ppublish
SO  - Mol Endocrinol. 2009 Apr;23(4):486-96. doi: 10.1210/me.2008-0407. Epub 2009 Jan 
      22.