Oberosler P, Hloch P, Ramsperger U, Stahl H
Fakultät für Biologie, Universität Konstanz, Germany.
EMBO J. 1993 Jun;12(6):2389-96. doi: 10.1002/j.1460-2075.1993.tb05893.x.
p53 has been reported to inhibit the DNA helicase intrinsic to simian virus 40 large tumor antigen (T antigen). We found that inhibition is not restricted to T antigen, but also affects several other DNA and RNA helicases. Complexing of the helicases by the p53 protein as a possible inactivation mechanism could be excluded. Instead, the anti-helicase activity can be explained by our finding that p53 binds with high affinity to single-stranded nucleic acids and has a strong DNA.DNA and RNA.RNA annealing activity. We could also show that p53 is able to alter the secondary structure of RNA and/or to influence dynamic RNA-RNA interactions. These results, and the fact that the affinity of p53 to RNA is about one order of magnitude higher than to single-stranded DNA, imply an RNA-specific function of p53 in vivo.
据报道，p53可抑制猿猴病毒40大肿瘤抗原（T抗原）所固有的DNA解旋酶。我们发现这种抑制作用并不局限于T抗原，还会影响其他几种DNA和RNA解旋酶。p53蛋白与解旋酶形成复合物作为一种可能的失活机制可以被排除。相反，这种抗解旋酶活性可以通过我们的发现来解释，即p53与单链核酸具有高亲和力，并且具有很强的DNA-DNA和RNA-RNA退火活性。我们还可以证明p53能够改变RNA的二级结构和/或影响动态RNA-RNA相互作用。这些结果，以及p53对RNA的亲和力比对单链DNA的亲和力高约一个数量级这一事实，意味着p53在体内具有RNA特异性功能。
