ISSN:
1573-675X
Keywords:
Apoptosis
;
DNA fragmentation
;
DNase γ
;
endonuclease
;
Xenopus laevis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract We recently found that two apoptotic DNase γ-like endonucleases (36 and 38kDa DNases) were present in Xenopus laevis larval and adult liver cell nuclei and that their activities increased in metamorphic climax. Here, we purified the main DNase γ-like endonuclease from Xenopus laevis liver cell nuclei and characterized its physical and enzymatic properties in detail. The molecular mass of Xenopus liver nuclear endonuclease was 38,000 daltons as determined by SDS-polyacrylamide gel electrophoresis. A native molecular mass of 35,000 was estimated by gel filtration. The purified Xenopus liver endonuclease was a neutral one and required both Ca2+ and Mg2+ for DNase activity. Unlike the mammalian DNase γ, the Ca2+/Mg2+ requirement could not be supplied by Mn2+. The inhibition profiles by aurintricarboxylic acid, sodium citrate and divalent metal ions such as Co2+, Ni2+, Cu2+ and Zn2+ were similar to those of mammalian DNase γ. These results suggest that this endonuclease is a Xenopus laevis homolog of the mammalian apoptotic endonuclease DNase γ.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009663204558
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