Tuteja N, Huang N W, Skopac D, Tuteja R, Hrvatic S, Zhang J, Pongor S, Joseph G, Faucher C, Amalric F
International Centre for Genetic Engineering and Biotechnology, Area Science Park, Trieste, Italy.
Gene. 1995 Jul 28;160(2):143-8. doi: 10.1016/0378-1119(95)00207-m.
The cDNA encoding human DNA helicase IV (HDH IV), a 100-kDa protein which unwinds DNA in the 5' to 3' direction with respect to the bound strand, was cloned and sequenced. It was found to be identical to the human cDNA encoding nucleolin, a ubiquitous eukaryotic protein essential for pre-ribosome assembly. HDH IV/nucleolin can unwind RNA-RNA duplexes, as well as DNA-DNA and DNA-RNA duplexes. Phosphorylation of HDH IV/nucleolin by cdc2 kinase and casein kinase II enhanced its unwinding activity in an additive way. The Gly-rich C-terminal domain possesses a limited ATP-dependent duplex-unwinding activity which contributes to the helicase activity of HDH IV/nucleolin.
编码人DNA解旋酶IV（HDH IV）的cDNA被克隆并测序，HDH IV是一种100 kDa的蛋白质，它相对于结合链以5'至3'方向解旋DNA。发现它与编码核仁素的人cDNA相同，核仁素是一种普遍存在的真核蛋白质，对核糖体前体组装至关重要。HDH IV/核仁素可以解旋RNA-RNA双链体，以及DNA-DNA和DNA-RNA双链体。cdc2激酶和酪蛋白激酶II对HDH IV/核仁素的磷酸化以累加方式增强了其解旋活性。富含甘氨酸的C末端结构域具有有限的ATP依赖性双链体解旋活性，这有助于HDH IV/核仁素的解旋酶活性。
