Distribution of neuroendocrine regulatory peptide-1 and -2, and proteolytic processing of their precursor VGF protein in the rat.
Neuroendocrine regulatory peptide (NERP)-1 and NERP-2 are biologically active peptides recently discovered by peptidomic analysis. NERPs are processed out from the 594-residue VGF protein which contains many prohormone convertase cleavage motifs. VGF-deficient mice exhibit a hypermetabolic and infertile phenotype, for which VGF protein-derived peptides including NERPs are presumably responsible. To provide a solid basis for elucidating physiological roles of NERPs, we investigated rat VGF protein processing by chromatographic and mass spectrometric analysis, and immunoblotting, using antibodies against NERPs and the VGF protein C-terminus (VGF-C). Cellular and tissue distribution of immunoreactive (ir) NERPs were also analyzed in the rat. Both ir-NERP-1 and ir-NERP-2, which occur abundantly in the CNS and pituitary, moderately in the gastrointestinal (GI) tract, were mainly localized in neuronal structures. Major endogenous forms of ir-NERPs in the brain and GI tract were identified as NERP-1, NERP-2, and big NERP-2 (NERP-1 + NERP-2), with NERP-1 and big NERP-2 being predominant. Regarding ir-VGF-C peptides, VGF[588-617], VGF[556-617], and VGF[509-617] were found to be major forms. Immunoblotting with the NERP-2 and VGF-C antibodies revealed processing intermediates of 10-37 kDa. Taken together, we deduce that VGF protein is primarily cleaved at 10 sites through the processing pathway common to the brain and GI tract.
Mishiro-Sato
Emi
E
Department of Molecular Pharmacology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
Sasaki
Kazuki
K
Matsuo
Takashi
T
Kageyama
Haruaki
H
Yamaguchi
Hideki
H
Date
Yukari
Y
Matsubara
Masako
M
Ishizu
Takehiro
T
Yoshizawa-Kumagaye
Kumiko
K
Satomi
Yoshinori
Y
Takao
Toshifumi
T
Shioda
Seiji
S
Nakazato
Masamitsu
M
Minamino
Naoto
N
D000818:Animals; D001923:Brain Chemistry / Q000502:physiology; D041981:Gastrointestinal Tract / Q000166:cytology / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism*; D009479:Neuropeptides / Q000737:chemistry / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010902:Pituitary Gland / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D014018:Tissue Distribution / Q000502:physiology
D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D010455:Peptides; D011498:Protein Precursors; C062040:Vgf protein, rat; C523894:neuroendocrine regulatory peptide-1, rat; C523896:neuroendocrine regulatory peptide-2, rat