Adolf-Butenandt-Institute and Centre for Integrated Protein Science (CiPSM) Ludwig-Maximilians University, Munich, Germany.
Bioessays. 2010 Aug;32(8):709-17. doi: 10.1002/bies.201000029.
Does the three-dimensional (3D) conformation of interphase chromosomes merely reflect their function or does it actively contribute to gene regulation? The analysis of sex chromosomes that are subject to chromosome-wide dosage compensation processes promises new insight into this question. Chromosome conformations are dynamic and largely determined by association of distant chromosomal loci in the nuclear space or by their anchoring to the nuclear envelope, effectively generating chromatin loops. The type and extent of such interactions depend on chromatin-bound transcription regulators and therefore reflects function. Dosage compensation adjusts the overall transcription activity of X chromosomes to assure balanced expression in the two sexes. Initial analyses of mammalian and Drosophila X chromosomes have led to the hypothesis that their conformations may not only reflect their functional state but may in turn contribute to the coordination of chromosome-wide tuning of transcription.
染色质的三维（3D）构象仅仅反映其功能，还是对基因调控有积极贡献？对受全染色体剂量补偿过程影响的性染色体的分析有望为这个问题提供新的见解。染色体构象是动态的，主要取决于核空间中远距离染色体位置的关联或它们与核膜的锚定，有效地产生染色质环。这种相互作用的类型和程度取决于结合在染色质上的转录调节剂，因此反映了功能。剂量补偿调整 X 染色体的整体转录活性，以确保在两性中平衡表达。对哺乳动物和果蝇 X 染色体的初步分析导致了这样的假设，即它们的构象不仅可以反映其功能状态，而且可以反过来有助于协调全染色体转录的调整。
