An in vitro system derived from Friend erythroleukemia cells to study messenger RNA stability

A system consisting of 40-80S messenger ribonucleoprotein particles (mRNP) from stationary Friend erythroleukemia (FEL) cells was used to investigate the stability of mRNA in vitro. The majority of mRNP mRNAs were found to be stable when incubated for periods of up to ninety minutes at 37 degrees. Nonetheless, many mRNAs are greatly reduced in abundance, including ones for eucaryotic elongation factor Tu (eEF-Tu) and the 73-78 kDa polypeptide commonly found in association with the poly(A) tails of mRNA. A divalent cation dependent ribonuclease (probably an endoribonuclease) could be washed off mRNP by treatment of the particles with 0.5M NaCl. The mRNAs contained in the resultant salt washed mRNPs, including eEF-Tu, were stable when incubated in vitro.