Koonin E V, Zhou S, Lucchesi J C
National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, MD 20894, USA.
Nucleic Acids Res. 1995 Nov 11;23(21):4229-33. doi: 10.1093/nar/23.21.4229.
Using computer methods for detecting conserved amino acid sequence motifs, we show that the chromatin organization modifier (chromo) domain that has been previously identified in several proteins involved in transcription down-regulation is present in a much larger group of (putative) chromatin-binding proteins, some of which are positive rather than negative regulators of transcription. The most interesting new members of the chromo superfamily are Drosophila male-specific lethal (MSL-3) protein involved in the X chromosome gene dosage compensation in the males and human retinoblastoma-binding protein RBP-1. We show that the chromo domain is duplicated in several chromatin-binding proteins and use this observation to interpret recent results on chromatin binding obtained with chimeric chromo domain-containing proteins. We hypothesize that the chromo domain may be a vehicle that delivers both positive and negative transcription regulators to the sites of their action on chromatin.
通过使用计算机方法检测保守的氨基酸序列基序，我们发现，先前在几种参与转录下调的蛋白质中鉴定出的染色质组织修饰因子（chromo）结构域，存在于一个更大的（假定的）染色质结合蛋白群体中，其中一些是转录的正调控因子而非负调控因子。chromo超家族中最有趣的新成员是参与雄性X染色体基因剂量补偿的果蝇雄性特异性致死（MSL-3）蛋白和人类视网膜母细胞瘤结合蛋白RBP-1。我们发现chromo结构域在几种染色质结合蛋白中存在重复，并利用这一观察结果来解释最近用含嵌合chromo结构域的蛋白质获得的染色质结合结果。我们推测，chromo结构域可能是一种载体，可将正负转录调节因子都传递到它们在染色质上的作用位点。
