title: Retinoylation (covalent modification by retinoic acid) of Rho-GDIβ in the human myeloid leukemia cell line HL60 and its functional significance.
abstract: Retinoic acid (RA) has a variety of biological effects in mammalian cells and tissues. It is well known that RA induces differentiation of human acute promyelocytic leukemia (APL) HL60 cells, fresh human APL cells, and clinical remission in patients with APL. Retinoylation (acylation of proteins by RA) is a possible pathway for RA action. However, an understanding of the role that retinoylation plays in the actions of RA is lacking. In the current study, several retinoylated proteins were detected in RA-treated HL60 fractions following Mono Q anion exchange chromatography and analysis using two-dimensional polyacrylamide gel electrophoresis. One of the retinoylated proteins was identified as Rho-GDIβ (28kDa) by TOF-MS and co-migration with Rho-GDIβ (28kDa). Truncated Rho-GDIβ (23kDa, N∆19), a product of cleavage by caspase-3, was not retinoylated. RA covalently bound to the Thr2 residue in Rho-GDIβ (5kDa), which is the second product resulting from the cleavage of Rho-GDIβ (28kDa) by caspase-3. RA treatment increased the level of Rho-GDIβ (28kDa) and decreased the level of Rho-GDIβ (23kDa). RA did not induce caspase-3 activity or Rho-GDIβ mRNA expression. It is likely that retinoylation of Rho-GDIβ increases its metabolic stability.
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan. Electronic address: t-noriko@hoshi.ac.jp.
authors.forename: Noriko
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Ohba
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Imai
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Hasegawa
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamasaki
authors.affiliation: Laboratory of Physiological Chemistry, Institute of Medicinal Chemistry, Hoshi University, Shinagawa, Tokyo 142-8501, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kameoka
mesh_terms: D000215:Acylation / Q000187:drug effects / Q000502:physiology*; D000595:Amino Acid Sequence; D053148:Caspase 3 / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D018922:HL-60 Cells; D006801:Humans; D007951:Leukemia, Myeloid / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D062949:rho Guanine Nucleotide Dissociation Inhibitor beta; D014212:Tretinoin; D012313:RNA; D053148:Caspase 3
keywords: HL60; Post-translational modification of proteins; Retinoic acid; Retinoylated proteins; Rho-GDIβ