PMID- 14688273
OWN - NLM
STAT- MEDLINE
DCOM- 20040706
LR  - 20211203
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 279
IP  - 10
DP  - 2004 Mar 5
TI  - Phosphatidylinositol 3-kinase and mTOR signaling pathways regulate RNA polymerase 
      I transcription in response to IGF-1 and nutrients.
PG  - 8911-8
AB  - Regulation of ribosomal RNA gene transcription by RNA polymerase I (Pol I) is 
      fundamental to ribosome biogenesis and therefore protein translation capacity and 
      cell growth, yet little is known of the key signaling cascades involved. We show 
      here that insulin-like growth factor-1 (IGF-1)-induced Pol I transcription in 
      HEK293 cells is entirely dependent on phosphatidylinositol 3-kinase (PI3K) 
      activity and, additionally, is modulated by the mammalian target of rapamycin 
      (mTOR), which coordinates Pol I transcription with the availability of amino 
      acids. The mitogen-activated protein kinase (MAPK) pathway is weakly stimulated 
      by IGF-1 in these cells and partly contributes to Pol I transcription regulation. 
      Activation of Pol I transcription by IGF-1 results from enhancement of the 
      activity of the Pol I transcription machinery and increased occupancy by SL1 of 
      the endogenous tandemly repeated ribosomal promoters in vivo. The inputs from 
      PI3K, mTOR, and MAPK pathways converge to direct appropriate rRNA gene expression 
      by Pol I in the nucleolus of mammalian cells in response to environmental cues, 
      such as growth factors and nutrients.
FAU - James, Martyn J
AU  - James MJ
AD  - Division of Gene Regulation and Expression, Wellcome Trust Biocentre, Faculty of 
      Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom.
FAU - Zomerdijk, Joost C B M
AU  - Zomerdijk JC
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20031219
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (RNA, Spliced Leader)
RN  - 67763-96-6 (Insulin-Like Growth Factor I)
RN  - EC 2.7.- (Protein Kinases)
RN  - EC 2.7.1.1 (MTOR protein, human)
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
RN  - EC 2.7.7.6 (RNA Polymerase I)
SB  - IM
EIN - J Biol Chem. 2020 May 15;295(20):7178. PMID: 32414913
MH  - Cell Line
MH  - Gene Expression Regulation/drug effects
MH  - Humans
MH  - Insulin-Like Growth Factor I/*pharmacology
MH  - MAP Kinase Signaling System
MH  - Phosphatidylinositol 3-Kinases/*metabolism
MH  - Promoter Regions, Genetic
MH  - Protein Kinases/*metabolism
MH  - RNA Polymerase I/*biosynthesis/genetics
MH  - RNA, Spliced Leader
MH  - Signal Transduction
MH  - TOR Serine-Threonine Kinases
MH  - Transcription, Genetic/drug effects
EDAT- 2003/12/23 05:00
MHDA- 2004/07/09 05:00
CRDT- 2003/12/23 05:00
PHST- 2003/12/23 05:00 [pubmed]
PHST- 2004/07/09 05:00 [medline]
PHST- 2003/12/23 05:00 [entrez]
AID - S0021-9258(17)47795-7 [pii]
AID - 10.1074/jbc.M307735200 [doi]
PST - ppublish
SO  - J Biol Chem. 2004 Mar 5;279(10):8911-8. doi: 10.1074/jbc.M307735200. Epub 2003 
      Dec 19.