skip to main content
語言:
資源種類 顯示結果: 顯示結果: 查詢種類 索引

Molecular variation and the evolution of newly developing sex chromosomes of Drosophila miranda.

Soojin. Yi The University of Chicago. 2000

Dissertation Abstracts International 61-07B.

線上取得

  • 題名:
    Molecular variation and the evolution of newly developing sex chromosomes of Drosophila miranda.
  • 著者: Soojin. Yi
  • The University of Chicago.
  • 主題: Biology, Genetics
  • 所屬期刊: Dissertation Abstracts International 61-07B.
  • 描述: The species Drosophila miranda possesses a new set of sex chromsomes, called the neo-sex chromosomes. This has resulted from a unique chromosomal fusion between the Y chromosome and one of Muller's C element autosomal pair. Several pieces of evidence from previous cytogenetic and molecular investigations suggested that the neo-sex chromosomes of D. miranda are in their early stage of becoming fully differentiated sex chromosomes. I extended molecular analyses of these newly evolving sex chromosomes, focusing especially on the molecular variation of marker genes on the neo-sex chromosomes, in order to evaluate different theoretical explanations accounting for the differentiation of the sex chromosomes. It is shown in this dissertation that the genes on the neo-Y chromosome show a reduced level of DNA sequence variation compared to X-linked and autosomal genes. The genes on the neo-X chromosome investigated in this dissertation showed similarly reduced levels of variation. I discuss these findings in the context of different models of Y chromosome degeneration as well as the evolution of dosage compensation on the counterpart X chromosome. In addition I characterize several population genetic parameters of D. miranda to provide a framework to understand molecular variation of this species. One interesting phenomenon that emerged from this molecular dissection of D. miranda is that some genes appear to have transposed to different chromosomes from their ancestral locations. A selective hypothesis to account for this phenomenon in the context of the evolution of the neo-sex chromosomes is proposed and a detailed analysis of one case is carried out. Both genomic and population genetics approaches support the hypothesis that directional selection is responsible for the observed transposition of genes originally linked to the neo-sex chromosomes of D. miranda.
  • 出版者: Thesis (Ph.D.)--The University of Chicago, 2000.
  • 建立日期: 2000
  • 格式: 157 p..
  • 語言: 英文
  • 識別號: ISBN0599843977
  • 資源來源: NUTN ALEPH
連結
返回到檢索清單
    臺南大學版權所有 © 2016 NUTN All Rights Reserved

正在檢索遠程資料庫，請稍等