title: Expression and proteasomal degradation of the major vault protein (MVP) in mammalian oocytes and zygotes.
abstract: Major vault protein (MVP), also called lung resistance-related protein is a ribonucleoprotein comprising a major part (>70%) of the vault particle. The function of vault particle is not known, although it appears to be involved in multi-drug resistance and cellular signaling. Here we show that MVP is expressed in mammalian, porcine, and human ova and in the porcine preimplantation embryo. MVP was identified by matrix-assisted laser-desorption ionization-time-of-flight (MALDI-TOF) peptide sequencing and Western blotting as a protein accumulating in porcine zygotes cultured in the presence of specific proteasomal inhibitor MG132. MVP also accumulated in poor-quality human oocytes donated by infertile couples and porcine embryos that failed to develop normally after in vitro fertilization or somatic cell nuclear transfer. Normal porcine oocytes and embryos at various stages of preimplantation development showed mostly cytoplasmic labeling, with increased accumulation of vault particles around large cytoplasmic lipid inclusions and membrane vesicles. Occasionally, MVP was associated with the nuclear envelope and nucleolus precursor bodies. Nucleotide sequences with a high degree of homology to human MVP gene sequence were identified in porcine oocyte and endometrial cell cDNA libraries. We interpret these data as the evidence for the expression and ubiquitin-proteasome-dependent turnover of MVP in the mammalian ovum. Similar to carcinoma cells, MVP could fulfill a cell-protecting function during early embryonic development.
authors.affiliation: Department of Animal Science, University of Missouri, Columbia, MO 65203, USA. SutovskyP@missouri.edu
authors.forename: Peter
authors.initials: P
authors.lastname: Sutovsky
authors.forename: Gaurishankar
authors.initials: G
authors.lastname: Manandhar
authors.forename: Jozef
authors.initials: J
authors.lastname: Laurincik
authors.forename: Juraj
authors.initials: J
authors.lastname: Letko
authors.forename: Jose Nestor
authors.initials: JN
authors.lastname: Caamaño
authors.forename: Billy N
authors.initials: BN
authors.lastname: Day
authors.forename: Liangxue
authors.initials: L
authors.lastname: Lai
authors.forename: Randall S
authors.initials: RS
authors.lastname: Prather
authors.forename: Kathy L
authors.initials: KL
authors.lastname: Sharpe-Timms
authors.forename: Randall
authors.initials: R
authors.lastname: Zimmer
authors.forename: Miriam
authors.initials: M
authors.lastname: Sutovsky
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western / Q000379:methods; D018929:Cell Culture Techniques; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005307:Fertilization in Vitro; D005455:Fluorescent Antibody Technique; D006801:Humans; D008322:Mammals / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes / Q000737:chemistry / Q000378:metabolism*; D009866:Oogenesis; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013552:Swine; D020394:Vault Ribonucleoprotein Particles / Q000378:metabolism*; D015053:Zygote / Q000378:metabolism*; D000099187:Major Vault Protein
chemical_list: D020394:Vault Ribonucleoprotein Particles; D000099187:Major Vault Protein