Vol 45(2011) N 6 p. 933-940;
M.G. Sharapov*, V.I. Novoselov, E.E. Fesenko, V.K. Ravin
Two Isoforms of Peroxiredoxin 6 of Xenopus laevisInstitute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142290 Russia
Received - 2011-02-14; Accepted - 2011-03-31
The genome of Xenopus laevis codes for two genes of peroxiredoxin 6, i.e., xen1 (Acc. no. EMBL Data Bank-BCO54278) and xen2 (Acc. no. EMBL Data Bank-BCO54309). Both the genes were cloned and expressed in Escherichia coli. The amino acid sequences of Xen1 and Xen2 enzymes are identical by 95%, and they possess the same peroxidase activity as well as similar optimums of temperature, pH, and thermostability. The genes of peroxiredoxin 6 of Xenopus laevisconsiderably differ in the period of expression during ontogenesis; i.e., xen2 is expressed during every stage of development, somewhat more intensively after stages 0-5; the expression of xen1 is initiated later, i.e., during the developmental stages of 47-48 h. Expression of xen2 increases after the incubation of embryos in a medium with hydrogen peroxide. Comparison of the amino acid sequences of Xen1 and Xen2 proteins shows that only Xen2 can possess phospholipase activity because its amino acid sequence contain residues of the phospholipase A2 active center: Ser31, His25, and Asp139.
peroxiredoxins, gene expression, embryonic development, Xenopus laevis