2006-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/653934摘要：本研究計畫的目標，是要證明並鑑定負責建構精卵結合醣結構的專一性醣轉化&#37238;，同時進一步的闡明這些醣轉化&#37238;在卵巢以、及特別是在卵子形成過程中，的表現圖譜。 初步的授精作用是經由精子結合於卵上的zon pellucida (ZP)，此結合已知需要的特定的醣結構。絕大部分連結於ZP的醣結構，被證明帶有type 2醣鏈結構（Galb1-4GlcNAc）。許多這些修飾過後的尾端醣結構，已被證明和精卵的辨識結合有關。另外，type1醣鏈結構（Galb1-3GlcNAc）也被發現存在於ZP之上。另外，最近發現ZP上，存在有相當量的Sda醣抗原結構（NeuAca2-3(GalNAcb1-4)Galb1-4）。Sda結構已知僅分布於人類少數幾個器官，例如大腸、胃、腎臟、及紅血球。最特別的是，它們的表現呈現onco-developmentally regulated的情形。Sda醣結構存在於ZP上，令人十分好奇它可能的扮演的功能。 雖然這些表現於ZP上，負責精卵辨識結合的醣結構多已被解出；但其負責生成的醣轉化&#37238;，仍然有待進一步闡明。這些醣轉化&#37238;可能包<br> Abstract: The gamete interactions have been demonstrated to be mediated by the binding of lectin-like sperm proteins with carbohydrate moieties on the zona pellucida (ZP) of eggs. Although the structures of the carbohydrate epitopes involved in the sperm-egg interaction have been demonstrated, the identities of the glycosyltransferases that responsible for the formation of these carbohydrate structures have never been revealed. The goal of this project is to demonstrate the identity of the glycosyltransferases involved in the synthesis of the critical carbohydrate structure, which mediates the initial sperm-egg binding, and to further elucidate the expression profiles of these glycosyltransferases in ovary and during oogenesis. Murine sperm initiate fertilization by binding to the outer covering of the egg that known as murine zona pellucida (mZP). This binding is thought to require the interaction of O-glycans linked to a specific mZP glycoprotein (mZP3) with egg-binding proteins coating the sperm plasma membrane. The majority of the O-glycans that are linked to mZP3 has been shown to contain core type 2 sequences terminated with sialic acid, including LacNAc (Galb1-4GlcNAc), LacdiNAc [(GalNAcb1-4GlcNAc)2], Gala1-3Gal, and Sda antigen [NeuAca2-3(GalNAcb1-4)Galb1-4]. Many of these terminal sequences have been implicated previously in murine sperm–egg binding. Core type 1 O-glycans (Galb1-3GlcNAc) are also present and are generally unmodified, although some are terminated with sialic acid or b-linked N-acetylhexosamine. Eggs expressing human ZP (huZP) glycoprotein huZP3, derived from transgenic mice, bind murine but not human sperm, implying that huZP3 acquires the same O-glycans as native mZP3. The glycosyltransferases responsible for the formation of the critical structures mentioned above may include b-1,4-galactosyltransferase, b-1,3-N-acetylglucosaminyltransferase, b-1,3-galactosyltransferase, and Sda b-1,4-N-acetylgalactosaminyltransferase. Most of these are known to comprise a family of homologous glycosyltransferases. Our Lab has focused on the investigation of human glycosyltransferases, which participate in the syntheses of several critical carbohydrate structures expressing on cell surfaces, during the past ten years. We will extend our expertise to investigate the identities of the glycosyltransferase genes that involve in the formation of important carbohydrate structures on mouse ZP. The specific aims of this component project are to accomplish the following investigation: a) Elucidation of the specific glycosyltransferases gene identities that involve in the synthesis and branching of type 1 and type 2 carbohydrate structures on mouse ZP. b) Identification of the Sda b4GalNAcT gene structure responsible for the expression of the Sda carbohydrate structures on ZP. c) Profiling the expression patterns of the glycosyltransferase genes responsible for modifying ZP carbohydrate structures in ovary and during oogenesis. d) Preparation of rec醣轉化&#37238精卵結合 醣結構gamete interactionsglycosyltransferases