Identification and NH2-terminal amino acid sequence of three insulin-like growth factor-binding proteins in porcine serum.
Three distinct species of IGFBP in porcine serum were identified by NH2-terminal amino acid sequence analysis. The IGFBPs identified include pIGFBP-2 (34 kDa), three isoforms of pIGFBP-3 (43, 40 and 30 kDa) and two isoforms of pIGFBP-4 (30 and 26 kDa). The three isoforms of pIGFBP-3 were found to have a common NH2-terminal amino acid sequence, as were the two isoforms of pIGFBP-4. These results indicate that porcine serum contains a truncated form of IGFBP-3 and two forms of pIGFBP-4, similar to those previously isolated from human and rat serum. Furthermore, the presence of a truncated form(s) of the GH-dependent IGFBP-3 in porcine serum suggests that elucidating its origin and function may be important in understanding how IGFBPs affect the somatogenic actions of GH.
Coleman
M E
ME
Department of Dairy and Animal Science, Pennsylvania State University, University Park 16802.
Pan
Y C
YC
Etherton
T D
TD
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000097:blood* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D018969:Insulin-Like Growth Factor Binding Proteins; D008969:Molecular Sequence Data; D013002:Somatomedins / Q000378:metabolism; D013552:Swine
D002352:Carrier Proteins; D018969:Insulin-Like Growth Factor Binding Proteins; D013002:Somatomedins