The Molecular Basis of Differential Chromatin Condensation

9302219 Hamkalo将采取两种主要方法来开始研究高等真核生物差异染色体凝聚的分子基础。第一篇文章探讨了存在于多个氨基酸序列变体中的连接蛋白H1在差异凝聚中的假定作用。在实验室中产生的针对人类亚型的抗体将用于通过免疫荧光原位确定亚型分布，并通过免疫亲和方法选择含有单个亚型的染色质片段。将分析选定的片段，以确定特定DNA序列的分布，以确定亚型是否在功能上可区分。第二种方法旨在评估一种新的方法，用于分离特定的DNA序列作为染色质（核蛋白杂交），以选择灵长类着丝粒卫星富集的染色质片段。所提出的实验旨在鉴定脊椎动物差异染色体凝聚背后的蛋白质。差异凝聚染色质是染色体着丝粒、端粒和非活性基因的诊断特征。因此，参与差异凝聚的蛋白质可能在基因抑制中发挥结构作用和功能作用。＊＊＊

9302219 Hamkalo Two major approaches will be taken to begin an investigation of the molecular basis of differential chromosome condensation in higher eukaryotes. The first explores the putative role of the linker histone, H1, which exists in multiple amino acid sequence variants, in differential condensation. Antibodies generated in the laboratory against human subtypes will be used to determine subtype distribution in situ by immunofluoresence and to select by immunofaffinity methods chromatin fragments containing individual subtypes. Selected fragments will be analyzed for the distribution of specific DNA sequences in order to determine whether or not subtypes are functionally distinguishable. The second approach is designed to evaluate a novel method for the fractionation of specific DNA sequences as chromatin (nucleoprotein hybridization) in order to select primate centromeric satellite enriched chromatin fragments. %%% The experiments proposed are directed towards the identification of proteins that underly differential chromosome condensation in vertebrates. Differentially condensed chromatin is a diagnostic feature of chromosomal centromeres, telomeres and inactive genes. Thus, proteins involved in differential condensation may play a structural role as well as a functional role in the repression of genes. ***