IDENTIFICATION OF BINDING PARTNERS FOR THE AMINO TERMINUS OF HUMAN CENP-A

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 着丝粒指导蛋白质结构的组装，称为动粒，在有丝分裂期间介导染色体和纺锤体微管之间的相互作用。为了使姐妹染色体在细胞分裂期间忠实地分离到相对的子细胞，每条染色体必须具有单个着丝粒。组蛋白H3变体CENP-A被认为是主要表观遗传机制的一部分，通过该机制，通过形成着丝粒特异性核小体来指定着丝粒。CENP-A是如何特异性地装载到着丝粒中的还不清楚，CENP-A如何指导着丝粒的组装也不清楚。如前所述，CENP-A是组蛋白H3变体。它包含与组蛋白H3（60%）具有高度相似性的组蛋白折叠结构域，并且是核小体结构、缠绕DNA和适当地将CENP-A靶向至着丝粒所需的。相比之下，CENP-A的42个氨基酸的N-末端尾部与组蛋白H3仅具有有限的氨基酸相似性，并且尚未将功能分配给该区域。其他组蛋白的氨基末端被证明是修饰位点（乙酰化、甲基化和磷酸化），这些修饰位点被证明对染色体结构和基因表达很重要。 这是我们的目标，以确定结合伙伴，可能有助于深入了解CENP-A的功能，使用TAP标记的版本的CENP-A在HeLa细胞中表达。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Centromeres direct the assembly of the proteinaceous structure called the kinetochore that mediates the interaction between chromosomes and spindle microtubules during mitosis. In order for sister chromosomes to be faithfully segregated to opposing daughter cells during cell division, each chromosome must possess a single centromere. The histone H3 variant CENP-A is thought to comprise part of the primary epigenetic mechanism by which centromeres are specified by forming a centromere-specific nucleosome. How CENP-A is specifically loaded into centromeres is not understood, nor is how CENP-A might direct the assembly of kinetochores. As mentioned, CENP-A is a histone H3 variant. It comprises a histone fold domain which shares a high degree of similarity with histone H3 (60%) and is required for nucleosome structure, winding DNA, and appropriately targeting CENP-A to the centromere. In contrast, the 42 amino acid N-terminal tail of CENP-A shares only limited amino acid similarity to histone H3, and no function has yet been assigned to this region. The amino termini of other histones have been shown to be sites of modification (acetylation, methylation, and phosphorylation) that have proven important for chromosomal structure and gene expression. It is our goal to identify binding partners that might lend insight into the function of CENP-A using TAP-tagged versions of the CENP-A expressed in HeLa cells.