Enzymatic Reaction： 

Bovine pancreatic deoxyribonuclease is an endonuclease that preferentially splits phosphodiester linkages adjacent to a pyrimidine nucleotide, yielding 5’-phosphate terminated polynucleotides with a free hydroxyl group at the 3’ position. DNase I is secreted by exocrine glands, and found most abundantly in the pancreas and parotid. It is also present in lower quantities in other tissues (Chen and Liao 2006, and Nadano et al. 1993).

DNase is known to be involved in apoptosis and has been proposed to play a role in the regulation of actin polymerization in cells. In addition to its use in molecular biology, DNase I has been used as a treatment for cystic fibrosis, and systemic lupus erythematosus (Chen and Liao 2006).

Specificity:

bpDNase I is not base nor sequence specific; however, it does not cleave randomly. It shows preference for cleavage at the 5’ side of pyrimidines, and is particularly pronounced in alternative copolymers (Bernardi et al. 1975, and Lomonossoff et al. 1981). It has been shown that variations in the twist angle are recognized by DNase I (Dickerson and Drew 1981). The specificity of DNase I also depends on the divalent cations present. In the presence of Ca2+ and Mg2+, it causes single strand breaks, and in the presence of Mn2+ double strand breaks have been reported (Junowicz and Spencer 1973, and Campbell and Jackson 1980).

Applications:

DNA removal in primary cell isolation: decreases viscosity providing better yields

DNA removal in bioprocessing applications

Removing genomic DNA from RNA preparations prior to RT-PCR

in vitro transcription

Nick translation

DNase footprinting

Actin binding

UV crosslinking of proteins to nucleic acids

Radioactive labeling

艾美捷Worthington脫氧核糖核酸酶I特異性：

bpDNase I 不是堿基或序列特異性的；但是，它不會(huì)隨機(jī)切割。它顯示優(yōu)先在嘧啶的 5' 側(cè)進(jìn)行裂解，并且在替代共聚物中尤其明顯（Bernardi 等人 1975 和 Lomonossoff 等人 1981）。已經(jīng)表明，扭曲角的變化被 DNase I 識(shí)別（Dickerson 和 Drew 1981）。DNase I 的特異性還取決于存在的二價(jià)陽離子。在存在 Ca2+ 和 Mg2+ 的情況下，它會(huì)導(dǎo)致單鏈斷裂，而在存在 Mn2+ 的情況下會(huì)導(dǎo)致雙鏈斷裂（Junowicz 和 Spencer 1973，以及 Campbell 和 Jackson 1980）。

艾美捷Worthington脫氧核糖核酸酶I分子特征：

與人類、小鼠和大鼠類似，牛胰腺 DNase I 基因由 9 個(gè)外顯子組成，只有最后 8 個(gè)外顯子編碼該蛋白質(zhì)（De María 和 Arruti 2003）。新生蛋白通過由外顯子二編碼的 22 個(gè)氨基酸信號(hào)序列引導(dǎo)至分泌途徑細(xì)胞器。主要活性位點(diǎn)殘基 H166 由外顯子 6 編碼（De María 和 Arruti 2003 和 Kraehenbuhl 等人 1977）。盡管牛和其他哺乳動(dòng)物的外顯子長度幾乎相同，但內(nèi)含子的長度差異很大。TATA 盒序列位于外顯子 I 上游 35 bp（De María 和 Arruti 2003）。已經(jīng)提出影響編碼序列的多重剪接事件可能是下調(diào) DNase I 表達(dá)的機(jī)制（Liu 等人 1997）。

脫氧核糖核酸酶I相關(guān)研究：

肌動(dòng)蛋白

白蛋白，無核酸酶

脫氧核糖核酸酶 II

脫氧核糖核酸及相關(guān)產(chǎn)品

組蛋白

核酸酶，微球菌

核酸酶，S1

磷酸酶，堿性

磷酸二酯酶 I

磷酸二酯酶 II

蛋白酶K

逆轉(zhuǎn)錄酶，重組 HIV

核糖核酸酶A

核糖核酸酶 T1

核糖核酸酶，E-Rase™ RNase 混合物

核糖核酸