Isolation and identification of midkine and pleiotrophin in bovine follicular fluid.
Ovarian factors that promote growth of vascular smooth muscle cells were investigated. Two distinct heparin-binding polypeptides were isolated from bovine follicular fluid by successive chromatographies. N-Terminal and tryptic peptide fragment analysis of these polypeptides revealed that they are identical to midkine (MK) and pleiotrophin (PTN), respectively, which form a new family of heparin-binding growth/differentiation factors. Two N-terminally distinct forms of midkine were also identified in the bovine follicular fluid. The concentrations of MK and PTN in the bovine follicular fluid were estimated to be 125 micrograms/l and 400 micrograms/l, respectively. The present findings that MK and PTN are quite rich in the follicular fluid will provide a new insight into so far unclarified functions of MK and PTN, especially their roles in the maturation of ovarian follicles.
Ohyama
Y
Y
Second Department of Internal Medicine, Gunma University School of Medicine, Japan.
Miyamoto
K
K
Minamino
N
N
Matsuo
H
H
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis / Q000737:chemistry; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002417:Cattle; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D016207:Cytokines / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D015571:Follicular Fluid / Q000737:chemistry*; D006133:Growth Substances / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000078792:Midkine; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects; D006080:Ovarian Follicle / Q000502:physiology; D017421:Sequence Analysis
D000596:Amino Acids; D002352:Carrier Proteins; D016207:Cytokines; D006133:Growth Substances; C066845:pleiotrophin; D000078792:Midkine