title: Molecular characteristics and physiological functions of major royal jelly protein 1 oligomer.
abstract: Royal jelly contains numerous components, including proteins. Major royal jelly protein (MRJP) 1 is the most abundant protein among the soluble royal jelly proteins. In its physiological state, MRJP 1 exists as a monomer and/or oligomer. This study focuses the molecular characteristics and functions of MRJP 1 oligomer. MRJP 1 oligomer purified using HPLC techniques was subjected to the following analyses. The molecular weight of MRJP 1 oligomer was found to be 290 kDa using blue native-PAGE. MRJP 1 oligomer was separated into 55 and 5 kDa spots on 2-D blue native/SDS-PAGE. The 55 kDa protein was identified as MRJP 1 monomer by proteome analysis, whereas the 5 kDa protein was identified as Apisimin by N-terminal amino acid sequencing, and this protein may function as a subunit-joining protein within MRJP 1 oligomer. We also found that the oligomeric form included noncovalent bonds and was stable under heat treatment at 56 degrees C. Furthermore, MRJP 1 oligomer dose dependently enhanced and sustained cell proliferation in the human lymphoid cell line Jurkat. In conclusion, MRJP 1 oligomer is a heat-resistant protein comprising MRJP 1 monomer and Apisimin, and has cell proliferation activity. These findings will contribute to further studies analyzing the effects of MRJP 1 in humans.
authors.affiliation: Division of Health Sciences, Graduate School of Health Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: Shougo
authors.initials: S
authors.lastname: Tamura
authors.forename: Shizuka
authors.initials: S
authors.lastname: Amano
authors.forename: Toru
authors.initials: T
authors.lastname: Kono
authors.forename: Jun
authors.initials: J
authors.lastname: Kondoh
authors.forename: Kikuji
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Seiichi
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Tokiyoshi
authors.initials: T
authors.lastname: Ayabe
authors.forename: Takanori
authors.initials: T
authors.lastname: Moriyama
mesh_terms: D000818:Animals; D001516:Bees / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D015180:Electrophoresis, Gel, Two-Dimensional; D005227:Fatty Acids / Q000032:analysis*; D006801:Humans; D019476:Insect Proteins / Q000032:analysis* / Q000302:isolation & purification / Q000494:pharmacology*; D019169:Jurkat Cells; D000099219:Royal Jelly
chemical_list: D005227:Fatty Acids; D019476:Insect Proteins; D000099219:Royal Jelly