The lactate dehydrogenase-A (LDH-A) gene, whose product plays a pivotal role in anaerobic glycolysis and whose expression is frequently increased in human cancers, is highly regulated by second messengers at the transcriptional as well as post-transcriptional levels. The application's long-term objectives are to further elucidate the molecular basis responsible for the complex regulation of LDH-A mRNA stability/instability by the cAMP-activated signal transduction pathway involving protein kinase A (PKA). Based on our recent studies, this proposal aims to further delineate (a) post-transcriptional mechanisms controlling LDH-A mRNA stability/instability involving a cAMP-stabilizing region (CSR) which we recently identified in the 3'-untranslated region (3'-UTR) of LDH-A mRNA, and (b) mechanisms whereby recently identified CSR-binding proteins (CSR-BP) are phosphorylated and functionally modified by the interaction of PKA, and (c) elucidate a potential functional interaction between CSR and CSR-BPs. The experimental system in which the studies will be conducted is the rat C6 glioma cell line in which activators of the PKA signal transduction pathway cause a marked stabilization of relatively rapidly decaying LDH-A mRNA leading to significant increase of LDH-A mRNA half-life.
The Specific Aims i nclude: (a) functional analysis of a cis-regulatory module in the 3'-UTR (the CSR) that controls mRNA stability; (b) cloning followed by a structural and functional analysis of trans- regulatory CSR-binding proteins which might be instrumental in controlling LDH-A mRNA half-life; (c) structure/function analysis of the CSR-BPs; and (d) analysis of the role of PKA in modulating the functional activity of CSR-BPs. The studies will contribute to our understanding of gene regulation by cAMP and of regulation of intermediary metabolism.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM053115-06
Application #
6490089
Study Section
Biochemical Endocrinology Study Section (BCE)
Program Officer
Rhoades, Marcus M
Project Start
1996-05-01
Project End
2003-12-31
Budget Start
2002-01-01
Budget End
2002-12-31
Support Year
6
Fiscal Year
2002
Total Cost
$254,752
Indirect Cost
Name
Northwestern University at Chicago
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
005436803
City
Chicago
State
IL
Country
United States
Zip Code
60611