Studying fertilization in cell-free extracts: focusing on membrane/lipid raft functions and proteomics.
Xenopus oocytes, eggs, and embryos serve as an ideal model system to study several aspects of animal development (e.g., gametogenesis, fertilization, embryogenesis, and organogenesis). In particular, the Xenopus system has been extensively employed not only as a "living cell" system but also as a "cell-free" or "reconstitutional" system. In this chapter, we describe a protocol for studying the molecular mechanism of egg fertilization with the use of cell-free extracts and membrane/lipid rafts prepared from unfertilized, metaphase II-arrested Xenopus eggs. By using this experimental system, we have reconstituted a series of signal transduction events associated with egg fertilization, such as sperm-egg membrane interaction, activation of Src tyrosine kinase and phospholipase Cgamma, production of inositol trisphosphate, transient calcium release, and cell cycle transition. This type of reconstitutional system may allow us to perform focused proteomics (e.g., rafts) as well as global protein analysis (i.e., whole egg proteome) of fertilization in a cell-free manner. As one of these proteomics approaches, we provide a protocol for molecular identification of Xenopus egg raft proteins using mass spectrometry and database mining.
Sato
Ken-ichi
K
Research Center for Environmental Genomics, Kobe University, Japan.
Yoshino
Ken-ichi
K
Tokmakov
Alexander A
AA
Iwasaki
Tetsushi
T
Yonezawa
Kazuyoshi
K
Fukami
Yasuo
Y
D000818:Animals; D019556:COS Cells; D002457:Cell Extracts; D002474:Cell-Free System; D002522:Chlorocebus aethiops; D005260:Female; D005306:Fertilization / Q000502:physiology*; D008297:Male; D021962:Membrane Microdomains / Q000737:chemistry / Q000502:physiology*; D040901:Proteomics / Q000379:methods; D029867:Xenopus Proteins / Q000737:chemistry / Q000502:physiology*; D014982:Xenopus laevis
D002457:Cell Extracts; D029867:Xenopus Proteins