scholarly journals Identification of the S6 kinase activity stimulated in quiescent brine shrimp embryos upon entry to preemergence development as p70 ribosomal protein S6 kinase: Isolation of Artemia franciscana p70S6k cDNA

2001 ◽  
Vol 79 (2) ◽  
pp. 141-152
Author(s):  
Jorge Santiago ◽  
Thomas W. Sturgill
Keyword(s):  
Ribosomal Protein ◽  
Brine Shrimp ◽  
Kinase Activity ◽  
Artemia Franciscana ◽  
S6 Kinase ◽  
Ribosomal Protein S6 ◽  
Ribosomal Protein S6 Kinase

Ribosomal protein S6 kinase activity controls the ribosome biogenesis transcriptional program

Oncogene ◽  
2013 ◽  
Vol 33 (4) ◽  
pp. 474-483 ◽  
Author(s):  
C Chauvin ◽  
V Koka ◽  
A Nouschi ◽  
V Mieulet ◽  
C Hoareau-Aveilla ◽  
...  
Keyword(s):  
Ribosomal Protein ◽  
Ribosome Biogenesis ◽  
Kinase Activity ◽  
Transcriptional Program ◽  
S6 Kinase ◽  
Ribosomal Protein S6 ◽  
Ribosomal Protein S6 Kinase

scholarly journals Identification of the S6 kinase activity stimulated in quiescent brine shrimp embryos upon entry to preemergence development as p70 ribosomal protein S6 kinase: Isolation of Artemia franciscana p70S6k cDNA

2001 ◽  
Vol 79 (2) ◽  
pp. 141-152 ◽  
Author(s):  
Jorge Santiago ◽  
Thomas W Sturgill
Keyword(s):  
Brine Shrimp ◽  
Kinase Activity ◽  
State Level ◽  
Artemia Franciscana ◽  
Level Variation ◽  
S6 Kinase ◽  
Ribosomal Subunits ◽  
Ribosomal Protein S6 ◽  
Ribosomal S6 Kinase ◽  
Specific Polyclonal Antibody

We previously demonstrated that a protein kinase responsible for phosphorylating 40S ribosomal subunits is activated in quiescent Artemia franciscana embryos within 15 min of restoration of normal tonicity and incubation at 30°C. Here, we identify the activated S6 kinase as A. franciscana p70 ribosomal S6 kinase (p70S6k) subsequent to the isolation of an Artemia p70S6k cDNA. The protein conceptually translated from cDNA has 70% similarity and 64% identity to both Drosophila melanogaster and human p70S6k. Southern blot analysis is consistent with presence of a single p70S6k gene. Two transcripts of 5.4 and 2.7 kb were found. Abundance of both mRNAs increased dramatically around 4 h of preemergence development, and exhibited different steady-state level variation thereafter. Stimulated S6 kinase activity, partially purified by Superose 6 chromatography, correlated best with the slowest migrating, ~65 kDa, form detected by Western analysis using a specific polyclonal antibody made to a peptide from the predicted p70S6k NH2-terminus. Furthermore, the A. franciscana p70S6k was immunoprecipitated with the same antibody, showing in parallel an S6 kinase activity similar to peak profiles. We conclude that the stimulated S6 kinase activity is that of an ortholog of human p70S6k that may be involved in the regulation of protein synthesis during preemergence development in A. franciscana species.Key Words: p70 ribosomal S6 kinase cDNA, brine shrimp, development.

The adipose tissue triglyceride lipase ATGL/PNPLA2 is downregulated by insulin and TNF-α in 3T3-L1 adipocytes and is a target for transactivation by PPARγ

2006 ◽  
Vol 291 (1) ◽  
pp. E115-E127 ◽  
Author(s):  
Ji Young Kim ◽  
Kristin Tillison ◽  
Jun-Ho Lee ◽  
David A. Rearick ◽  
Cynthia M. Smas
Keyword(s):  
Adipose Tissue ◽  
Ribosomal Protein ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
S6 Kinase ◽  
Triglyceride Lipase ◽  
Ribosomal Protein S6 ◽  
Tnf Α ◽  
Adipose Tissue Triglyceride ◽  
Ribosomal Protein S6 Kinase

The minimal adipose phenotype of hormone-sensitive lipase (HSL)-null mice suggested that other hormonally responsive lipase(s) were present in adipocytes. Recent studies have characterized a new adipose tissue triglyceride lipase, ATGL/PNPLA2/destnutrin/iPLA2ζ/TTS2.2 (ATGL). We had previously cloned a novel adipose-enriched transcript by differential screening and recently determined its identity with murine ATGL. We report here on the regulation of ATGL by TNF-α and insulin in 3T3-L1 adipocytes and identify ATGL as a target for transcriptional activation by the key adipogenic transcription factor PPARγ. Insulin at 100 nM resulted in a marked decrease in ATGL transcript that was effectively blocked by inhibitors for PI 3-kinase and p70 ribosomal protein S6 kinase. TNF-α treatment decreased ATGL transcript in a time-dependent manner that paralleled TNF-α downregulation of PPARγ with a maximal decrease noted by 6 h. TNF-α effects on ATGL were attenuated by pretreatment with PD-98059, LY-294002, or rapamycin, suggesting involvement of the p44/42 MAP kinase, PI 3-kinase, and p70 ribosomal protein S6 kinase signals. To study transcriptional regulation of ATGL, we cloned 2,979 bp of the murine ATGL 5′-flanking region. Compared with promoterless pGL2-Basic, the −2979/+21 ATGL luciferase construct demonstrated 120- and 40-fold increases in activity in white and brown adipocytes, respectively. Luciferase reporter activities for a series of eight ATGL promoter deletions revealed that the −928/+21, −1738/+21, −1979/+21, and −2979/+21 constructs were transactivated by PPARγ. Our findings identify the novel lipase ATGL to be a target gene for TNF-α and insulin action in adipocytes and reveal that it is subject to transcriptional control by PPARγ-mediated signals.

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