title: Endogenous oligonucleotides of human milk and their possible biological function.
abstract: Oligonucleotides (ON) 4 to 60 nucleotides in length were isolated by ion-exchange chromatography on a column with Fractogel TSK DEAE-650 (M) from human milk which was hydrolyzed with proteinase K. ON from 60 to 16 nucleotides were degraded by RNase A but were resistant to DNase I, and, thus, they were ribooligonucleotides. In the presence of [gamma-32P]ATP, ON and heparin inhibited the phosphorylation of 38- and 20-kD milk proteins and failed to affect the phosphorylation of a 76-kD protein. Human milk is believed to contain polyanion-dependent and polyanion-independent protein kinases. The influence of the ON on the activity of the cytotoxic fraction of human milk alpha-lactalbumin towards human mammary gland carcinoma MCF-7 cells was studied. The ON inhibited the cytostatic and cytotoxic effects of alpha-lactalbumin. Synthetic oligonucleotides and heparin had similar effects. The endogenous ON are suggested to be involved in the regulation of cytotoxic activity of human milk.
authors.affiliation: Novosibirsk Institute of Bioorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia. kit@niboch.nsc.ru
authors.forename: Y Y
authors.initials: YY
authors.lastname: Kit
authors.forename: E V
authors.initials: EV
authors.lastname: Kuligina
authors.forename: A M
authors.initials: AM
authors.lastname: Onishchenko
authors.forename: L V
authors.initials: LV
authors.lastname: Yurchenko
authors.forename: I V
authors.initials: IV
authors.lastname: Romannikova
authors.forename: V A
authors.initials: VA
authors.lastname: Richter
authors.forename: V V
authors.initials: VV
authors.lastname: Vlassov
mesh_terms: D002852:Chromatography, Ion Exchange; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D008894:Milk Proteins / Q000378:metabolism*; D008895:Milk, Human / Q000737:chemistry* / Q000502:physiology*; D009843:Oligoribonucleotides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010766:Phosphorylation; D012259:Ribonuclease, Pancreatic
chemical_list: D008894:Milk Proteins; D009843:Oligoribonucleotides; D006493:Heparin; D012259:Ribonuclease, Pancreatic