Centromeres and Ovarian Cancer

着丝粒DNA的组成、组织和功能仍然是遗传学最后的前沿领域之一。 基因组学这项提案"着丝粒和卵巢癌"将调查着丝粒DNA的作用， 序列在卵巢癌中着丝粒和染色体分离的正确功能中起作用， 及其对卵巢癌进展的作用。着丝粒是一个功能单位， 染色体的可靠分离。不能正确地将染色体分配给子细胞导致 基因组不稳定性和非整倍性（染色体的获得或丢失），这是癌症的标志。功能性着丝粒 结构是由着丝粒表观遗传标记，结合到底层的DNA序列。在细胞 分裂时，微管与这些着丝粒结构相互作用，将染色体拉开。虽然 着丝粒的身份和功能依赖于表观遗传机制，最近的研究表明， 序列也具有功能性作用。然而，人类的着丝粒序列还没有被组装 线性重叠群，因为它们的重复DNA含量高，因此，精确的组成，组织， 和着丝粒DNA的功能仍有待阐明。我们将研究着丝粒DNA 序列在卵巢癌中的着丝粒功能和染色体分离中起作用。克服虚拟 在人类基因组计划中缺少着丝粒序列，P.I.发明了快速定量PCR 的方法和创新的下一代测序工具，专门研究着丝粒DNA 每个人类染色体的分子水平。利用这些先进的技术，我们 发现卵巢癌细胞的基因组在特定的染色体上表现出严重的着丝粒序列缺失， 染色体，特别是17号染色体。我们假设 这些特定的着丝粒突变在着丝粒的形成和功能中起关键作用，并导致 卵巢癌中17号染色体错误分离和基因组不稳定性。该研究将使用 使用CRISPR Cas9产生的具有着丝粒缺失的突变卵巢和输卵管细胞系。我们将 研究着丝粒缺失是否改变了着丝粒表观遗传标记形成的能力 着丝粒/动粒结构。我们将讨论这些突变细胞中着丝粒物质的丢失是否 影响基因组稳定性、染色体分离和转化。这些信息将开始提供 更好地理解着丝粒序列在细胞分裂和癌症遗传学中的作用。这些研究 将增强我们对着丝粒和染色体生物学的知识，并可能导致新的 研究癌症遗传缺陷的方法。

The composition, organization, and function of centromeric DNA remain one of the last frontiers of genomics. This proposal “Centromeres and Ovarian Cancer” will investigate the role centromere DNA sequences play in the correct function of centromeres and chromosome segregation in ovarian cancer, and its contribution to ovarian cancer progression. The centromere is the functional unit responsible for the faithful segregation of chromosomes. Failure to properly partition chromosomes to daughter cells results in genome instability and aneuploidy (gain or loss of chromosomes), a hallmark of cancers. Functional centromere structures are made of centromere epigenetic marks that bind to the underlying DNA sequence. During cell division, the microtubules interact with these centromeric structures and pull chromosomes apart. Although centromere identity and function rely on epigenetic mechanisms, recent studies suggest that centromere sequences have functional roles as well. However, human centromere sequences have not been assembled into linear contigs due to their high content of repetitive DNA, and thus, the precise composition, organization, and function of centromeric DNA remain to be elucidated. We will investigate the role centromere DNA sequences play in centromere function and chromosome segregation in ovarian cancer. To overcome the virtual absence of centromere sequence in the Human Genome Project, the P.I. has devised rapid, quantitative PCR- based methods and innovative Next Generation Sequencing tools to study specifically the centromeric DNA elements of each human chromosome at the molecular level. Using these pioneering technologies, we discovered that the genomes of ovarian cancer cells exhibit severe loss of centromere sequences in specific chromosomes, in particular chromosome 17, when compared to healthy matched-tissue. We hypothesize that these specific centromere mutations play a key role in centromere formation and function, and lead to chromosome 17 missegregation and genome instability seen in ovarian cancer. The proposed research will use mutant ovarian and fallopian tube cell lines with centromere deletions generated using CRISPR Cas9. We will investigate whether centromere loss alters the ability of centromeric epigenetic marks to form centromere/kinetochore structures. We will address whether loss of centromeric material in these mutant cells affects genome stability, chromosome segregation and transformation. This information will begin to provide a better understanding of the role’s centromere sequences play in cell division and cancer genetics. These studies will enhance our knowledge of centromeres and chromosomal biology and could potentially result in novel methodologies to study genetic defects in cancers.