scholarly journals Rheb interacts with Raf-1 kinase and may function to integrate growth factor- and protein kinase A-dependent signals.

1997 ◽  
Vol 17 (2) ◽  
pp. 921-933 ◽  
Author(s):  
W M Yee ◽  
P F Worley
Keyword(s):  
Growth Factor ◽  
Protein Kinase ◽  
Protein Kinase A ◽  
Immediate Early Gene ◽  
Early Gene ◽  
Immediate Early ◽  
Single Amino Acid ◽  
Ras Signaling ◽  
Differential Properties ◽  
Kinase A

Rheb is a recently described member of the Ras family that was originally identified as an immediate-early gene in brain but is also widely expressed in other tissues. Here we demonstrate that Rheb interacts with and appears to regulate Raf-1 kinase, an essential component of the H-Ras signaling pathway. In direct contrast to H-Ras, however, the interaction of Rheb with Raf-1 is potentiated by growth factors in combination with agents that increase cyclic AMP (cAMP) levels. Protein kinase A-dependent phosphorylation of serine 43 within the regulatory domain of Raf-1 reciprocally potentiates its interaction with Rheb and decreases its interaction with H-Ras. A single amino acid in the G2 effector domain is critical for the differential properties of Rheb. Since Rheb is an immediate-early gene, our studies suggest that Rheb functions in concert with H-Ras to dynamically integrate cAMP and growth factor signaling.

Regulation of Hepatic Glucose Production by Transforming Growth Factor Beta 1 via Protein Kinase A

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 2441-PUB ◽  
Author(s):  
QUAN PAN ◽  
YUNMEI CHEN ◽  
HUI YAN ◽  
WANBAO YANG ◽  
ZHENG SHEN ◽  
...  
Keyword(s):  
Growth Factor ◽  
Protein Kinase ◽  
Protein Kinase A ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Hepatic Glucose Production ◽  
Glucose Production ◽  
Hepatic Glucose ◽  
Growth Factor Beta ◽  
Kinase A

scholarly journals A novel 7-nucleotide motif located in 3' untranslated sequences of the immediate-early gene set mediates platelet-derived growth factor induction of the JE gene.

1992 ◽  
Vol 12 (12) ◽  
pp. 5288-5300 ◽  
Author(s):  
R R Freter ◽  
J C Irminger ◽  
J A Porter ◽  
S D Jones ◽  
C D Stiles
Keyword(s):  
Growth Factor ◽  
Immediate Early Genes ◽  
Immediate Early Gene ◽  
Early Gene ◽  
Platelet Derived Growth Factor ◽  
Immediate Early ◽  
Control Element ◽  
Gene Set ◽  
Cis Acting ◽  
Early Genes

A cohort of the serum and growth factor regulated immediate-early gene set is induced with slower kinetics than c-fos. Two of the first immediate-early genes characterized as such, c-myc and JE, are contained within this subset. cis-acting genomic elements mediating induction of the slower responding subset of immediate-early genes have never been characterized. Herein we characterize two widely separated genomic elements which are together essential for induction of the murine JE gene by platelet-derived growth factor, serum, interleukin-1, and double-stranded RNA. One of these elements is novel in several regards. It is a 7-mer, TTTTGTA, found in the proximal 3' sequences downstream of the JE stop codon. The 3' element is position dependent and orientation independent. It does not function in polyadenylation, splicing, or destabilization of the JE transcript. Copies of the 7-mer or its inverse are found at comparable 3' sites in 25 immediate-early genes that encode transcription factors or cytokines. Given its general occurrence, the 7-mer may be a required cis-acting control element mediating induction of the immediate-early gene set.

B-Raf-dependent regulation of the MEK-1/mitogen-activated protein kinase pathway in PC12 cells and regulation by cyclic AMP

1994 ◽  
Vol 14 (10) ◽  
pp. 6522-6530
Author(s):  
R R Vaillancourt ◽  
A M Gardner ◽  
G L Johnson
Keyword(s):  
Growth Factor ◽  
Protein Kinase ◽  
Map Kinase ◽  
Protein Kinase A ◽  
Pc12 Cells ◽  
Kinase Activation ◽  
Mitogen Activated Protein ◽  
Epidermal Growth ◽  
Camp Levels ◽  
Kinase A

Growth factor receptor tyrosine kinase regulation of the sequential phosphorylation reactions leading to mitogen-activated protein (MAP) kinase activation in PC12 cells has been investigated. In response to epidermal growth factor, nerve growth factor, and platelet-derived growth factor, B-Raf and Raf-1 are activated, phosphorylate recombinant kinase-inactive MEK-1, and activate wild-type MEK-1. MEK-1 is the dual-specificity protein kinase that selectively phosphorylates MAP kinase on tyrosine and threonine, resulting in MAP kinase activation. B-Raf and Raf-1 are growth factor-regulated Raf family members which regulate MEK-1 and MAP kinase activity in PC12 cells. Protein kinase A activation in response to elevated cyclic AMP (cAMP) levels inhibited B-Raf and Raf-1 stimulation in response to growth factors. Ras.GTP loading in response to epidermal growth factor, nerve growth factor, or platelet-derived growth factor was unaffected by protein kinase A activation. Even though elevated cAMP levels inhibited Raf activation, the growth factor activation of MEK-1 and MAP kinase was unaffected in PC12 cells. The results demonstrate that tyrosine kinase receptor activation of MEK-1 and MAP kinase in PC12 cells is regulated by B-Raf and Raf-1, whose activation is inhibited by protein kinase A, and MEK activators, whose activation is independent of cAMP regulation.

Sign in / Sign up

Export Citation Format

Share Document