A polypeptide growth inhibitor isolated from lactating bovine mammary gland (MDGI) is a lipid-carrying protein.
Mammary-derived growth inhibitor (MDGI), a polypeptide growth inhibitor isolated from lactating bovine mammary tissue, previously shown to have extensive sequence homology with fatty acid-binding proteins, was demonstrated to meet the criteria of a fatty acid-binding protein. The protein was found to bind [3H]palmitic acid in a saturable manner and to be complexed with endogeneous free fatty acids. [3H]palmitic acid, when bound to the protein, was more rapidly taken up by the target cells (human mammary carcinoma cells [MaTu]) than was free [3H]palmitic acid, suggesting a lipid carrier function for the inhibitor. It is suggested that the fatty acid-binding properties of MDGI may relate to its ability to inhibit cell growth in vitro and to regulate other cellular functions.
Böhmer
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FD
Department of Cell Biology, Academy of Sciences of the G.D.R.
Mieth
M
M
Reichmann
G
G
Taube
C
C
Grosse
R
R
Hollenberg
M D
MD
D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D002417:Cattle; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D006131:Growth Inhibitors / Q000302:isolation & purification / Q000378:metabolism; D007774:Lactation; D008321:Mammary Glands, Animal / Q000032:analysis*; D011247:Pregnancy
D002352:Carrier Proteins; D005227:Fatty Acids; D006131:Growth Inhibitors