The best characterized yeast guanine nucleotide releasing factor is CDC25, which acts on RAS and thereby stimulates cAMP production in Saccharomyces cerevisiae. In order to determine if CDC25 could be a specific GDP-GTP releasing factor for the mammalian proteins Ha-ras, Ki-ras, and N-ras, its functions were studied both in vitro and in NIH3T3 cells. The 561 amino acid composing the C-terminal domain of CDC25 (CDC25 C-domain) released guanine nucleotides (both GDP and GTP) from Ha-, Ki-, and N-ras but not from Rap1A, Rab5, and Rab11. CDC25 acted on oncogenically activated Ha-ras even if the last 23 amino acids (167-189) of the Ras proteins were not present. CDC25 transformed NIH3T3 cells; its transforming capacity was enhanced by overexpression of wild-type Ha-ras. CDC25 C-domain probably exerts its effects through the activation of cellular Ras proteins. These data suggest that the CDC25 C-domain can function as an upstream activator of Ras proteins in a heterologous system and therefore could be a useful tool to study the regulation of Ras activation by growth factor receptors.

Download full-text PDF

Source

Publication Analysis

Top Keywords

ras proteins
16
releasing factor
12
nih3t3 cells
12
cdc25 c-domain
12
cdc25
9
saccharomyces cerevisiae
8
guanine nucleotide
8
nucleotide releasing
8
factor mammalian
8
ras
6

Similar Publications

Anisotropic interactions for continuum modeling of protein-membrane systems.

J Chem Phys

December 2024

Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.

In this work, a model for anisotropic interactions between proteins and cellular membranes is proposed for large-scale continuum simulations. The framework of the model is based on dynamic density functional theory, which provides a formalism to describe the lipid densities within the membrane as continuum fields while still maintaining the fidelity of the underlying molecular interactions. Within this framework, we extend recent results to include the anisotropic effects of protein-lipid interactions.

View Article and Find Full Text PDF

Proto-oncogene KRAS, GTPase (KRAS) is one of the most intensively studied oncogenes in cancer research. Although several mouse models allow for regulated expression of mutant KRAS, selective isolation and analysis of transforming or tumor cells that produce the KRAS oncogene remains a challenge. In our study, we present a knock-in model of oncogenic variant KRAS that enables the "activation" of KRAS expression together with production of red fluorescent protein tdTomato.

View Article and Find Full Text PDF

Resistance-associated substitutions (RASs) are mutations within the hepatitis C (HCV) genome that may influence the likelihood of achieving a sustained virological response (SVR) with direct acting antiviral (DAA) treatment. Clinicians conduct RAS testing to adapt treatment regimens with the intent of improving the likelihood of cure. The Canadian Network Undertaking against Hepatitis C (CANUHC) prospective cohort consists of chronic HCV patients enrolled between 2015 and 2023 across 17 Canadian sites.

View Article and Find Full Text PDF

Background: Cerebral amyloid angiopathy (CAA), the accumulation of amyloid proteins in the cerebral vasculature, increases the risk of stroke and vascular cognitive impairment and dementia (VCID). Not only is there no treatment for CAA, but the condition is also highly comorbid with Alzheimer's disease (AD), and its presence may serve as a contraindication to treating patients with anti-amyloid therapies due to an increased risk of hemorrhage and edema. Therefore, it is crucial to identify novel treatments for individuals with CAA.

View Article and Find Full Text PDF

Lung cancer is the leading cause of cancer deaths in the United States. New targeted therapies against the once-deemed undruggable oncogenic KRAS are changing current therapeutic paradigms. However, resistance to targeted KRAS inhibitors almost inevitably occurs; resistance can be driven by tumor cell-intrinsic changes or by changes in the microenvironment.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!