Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.17.1.4 (
xanthine dehydrogenase
)
1,236
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
To better understand the mechanisms responsible for the success of female mosquitoes in their disposal of excess nitrogen, we investigated the role of alanine aminotransferase (ALAT) in blood-fed Aedes aegypti. Transcript and protein levels from the 2 ALAT genes were analyzed in sucrose- and blood-fed A. aegypti tissues. ALAT1 and ALAT2 exhibit distinct expression patterns in tissues during the first gonotrophic cycle. Injection of female mosquitoes with either double-stranded RNA (dsRNA)-ALAT1 or dsRNA ALAT2 significantly decreased mRNA and protein levels of ALAT1 or ALAT2 in fat body, thorax, and Malpighian tubules compared with dsRNA firefly luciferase-injected control mosquitoes. The silencing of either A. aegypti ALAT1 or ALAT2 caused unexpected phenotypes such as a delay in blood digestion, a massive accumulation of uric acid in the midgut posterior region, and a significant decrease of nitrogen waste excretion during the first 48 h after blood feeding. Concurrently, the expression of genes encoding
xanthine dehydrogenase
and ammonia transporter (Rhesus 50
glycoprotein
) were significantly increased in tissues of both ALAT1- and ALAT2-deficient females. Moreover, perturbation of ALAT1 and ALAT2 in the female mosquitoes delayed oviposition and reduced egg production. These novel findings underscore the efficient mechanisms that blood-fed mosquitoes use to avoid ammonia toxicity and free radical damage.-Mazzalupo, S., Isoe, J., Belloni, V., Scaraffia, P. Y. Effective disposal of nitrogen waste in blood-fed Aedes aegypti mosquitoes requires alanine aminotransferase.
...
PMID:Effective disposal of nitrogen waste in blood-fed Aedes aegypti mosquitoes requires alanine aminotransferase. 2631 Feb 69
Dickkopf (DKK) 3 is a DKK
glycoprotein
family member that controls cell fate during embryogenesis and exerts opposing effects on survival in a cell type-dependent manner; however, the mechanisms governing its pro-apoptosis versus pro-survival functions remain unclear. Here, we investigated DKK3 function in Li21 hepatoma cells and tPH5CH immortalized hepatocytes. DKK3 knockdown by siRNA resulted in reactive oxygen species accumulation and subsequent apoptosis, which were abrogated by administration of the antioxidant N-acetyl-cysteine. Moreover, forced DKK3 over-expression induced resistance to hydrogen peroxide (H
2
O
2
)-induced apoptosis. Expression analysis by cDNA microarray showed that
xanthine dehydrogenase
(
XDH
) expression was significantly lower in Li21 and tPH5CHDKK3-over-expressing cells in response to H
2
O
2
treatment when compared to that in their respective mock-transfected controls, whereas a marked increase was observed in H
2
O
2
-treated DKK3 knockdown cells. Thus, these data suggest that DKK3 promotes cell survival during oxidative stress by suppressing the expression of the superoxide-producing enzyme
XDH
.
...
PMID:Dickkopf 3 attenuates xanthine dehydrogenase expression to prevent oxidative stress-induced apoptosis. 2829 63
