You are here:
THE EFFECT OF TARGETED KNOCKOUT MUTATION ON THE TRANSCRIPTIONAL PROFILE OF THE KIDNEY IN TSC2 MUTANT LONG-EVANS (EKER) RATS.
Citation:
Sen, B., D C. Wolf, AND S D. Hester. THE EFFECT OF TARGETED KNOCKOUT MUTATION ON THE TRANSCRIPTIONAL PROFILE OF THE KIDNEY IN TSC2 MUTANT LONG-EVANS (EKER) RATS. Presented at Society of Toxicologic Pathology Annual Meeting, Savannah, GA, 06/15-19/03.
Description:
The effect of a targeted knockout mutation on the transcriptional profile of the kidney in
Tsc2 mutant Long-Evans (Eker) rats.
Renal cell carcinoma (RCC) is the most common tumor of the adult kidney, accounting
for up to 80% of malignant renal neoplasms. Hereditary RCC in the Eker rat, which bear
a number of cellular, molecular and phenotypic similarities to some human RCC, results
from an inherited insertional mutation in the Tsc2 tumor suppressor gene. The Eker rat
model has provided a valuable experimental model to characterize the function of the
Tsc2 gene product, tuberin, and to elicit the mechanisms of tumorigenesis caused by inactivation of the Tsc2 gene. We hypothesize that multiple signaling pathways will be
affected by the Tsc2 knockout in the rat kidney. Gene expression profiles resulting from
the Tsc2 mutation were determined using AgilentTM cDNA arrays containing 14000
genes and ESTs. Total RNA from wild type (+/+) and heterozygous mutant (+/-) rats was reverse transcribed into CDNA using standard techniques. A two dye labeling protocol
was used to incorporate fluorescent tags into the cDNA. Gene expression as a function
of fluorescent signal intensity ratio was generated using an Axon scanner and analysis
performed with GeneSpringTM analysis software. On examination of the global changes in
gene expression pattern, it was observed that of the 8372 specified rodent genes on the
array, 7% of the genes were up regulated and 14% were down regulated by 2 fold or
involved in cell growth and maintenance, cell connnunication and cell surface linked
signal transduction. Of these 0.3% (27) of the genes were greater than IO fold up regulated
in the mutant kidneys. These highly expressed genes included GADD45y which is involved
in cell death, as well as several kinases and transport related genes. The basal expression level of genes involved in pathways up and downstream of known and suspected tuberin activity, namely Rab5, rho B and cdc42, had a 2-fold increased expression. These data suggest that the loss of function of a single gene can have an impact on the molecular functioning of the cell more than just the loss of the specific function of the target gene.
(This abstract does not reflect policy or opinions of the USEPA).