Putative human blue-light photoreceptors hCRY1 and hCRY2 are flavoproteins
Putative human blue-light photoreceptors hCRY1 and hCRY2 are flavoproteins
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DOI：
10.1021/bi962209o
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发表时间：
1996-11-05
期刊：
影响因子：
2.9
通讯作者：
Sancar, A
中科院分区：
文献类型：
--
作者：
Hsu, DS;Zhao, XD;Sancar, A
最近，鉴定了与光裂合酶/蓝光光感受器家族具有高序列同源性的人cDNA克隆。由该基因编码的推定蛋白质显示出与果蝇（6-4）光裂合酶惊人高的同源性（48%同一性）[Todo等（1996）Science 272，109-112]。我们现在已经确定了第二个人类基因，其氨基酸序列与第一个基因具有73%的同一性，并将这两个基因分别命名为p21和p22。纯化相应的蛋白质hb 1和hb 2，并表征为麦芽糖结合融合蛋白。与光裂合酶/蓝光光感受器家族的其他成员类似，发现这两种蛋白质都含有FAD和蝶呤辅因子。与植物蓝光光感受器一样，hb 1和hb 2都缺乏对环丁烷嘧啶二聚体和（6-4）光产物的光解酶活性。我们的结论是，这些新发现的光解酶/光感受器家族成员不是光解酶，而是可能作为人类的蓝光光感受器。
Recently, a human cDNA clone with high sequence homology to the photolyase/blue-light photoreceptor family was identified. The putative protein encoded by this gene exhibited a strikingly high (48% identity) degree of homology to the Drosophila melanogaster (6-4) photolyase [Todo et al. (1996) Science 272, 109-112]. We have now identified a second human gene whose amino acid sequence displays 73% identity to the first one and have named the two genes CRY1 and CRY2, respectively. The corresponding proteins hCRY1 and hCRY2 were purified and characterized as maltose-binding fusion proteins. Similar to other members of the photolyase/blue-light photoreceptor family, both proteins were found to contain FAD and a pterin cofactor. Like the plant blue-light photoreceptors, both hCRY1 and hCRY2 lacked photolyase activity on the cyclobutane pyrimidine dimer and the (6-4) photoproduct. We conclude that these newly discovered members of the photolyase/photoreceptor family are not photolyases and instead may function as blue-light photoreceptors in humans.