Metabolism of polyadenylated mRNA in growing human lymphocytes

Biochim Biophys Acta. 1979 Mar 28;562(1):80-91. doi: 10.1016/0005-2787(79)90128-x.

Abstract

The kinetics of degradation of newly synthesized, cytoplasmic polyadenylated RNA have been examined in normal human lymphocytes stimulated to grow with phytohemagglutinin. A single class of poly(A)-bearing RNA was identified with a half-life of approximately 50 h. In the presence of actinomycin D, the half-life was 5 to 6 h, and virtually no decay of pulse-labeled material was detectable after 6 h of chase incubation with cordycepin. These findings contrast sharply with data obtained from other growing human cells used as controls: polyadenylated mRNA in MOLT-4 cells, a cultured line of T lymphocytes, had a half-life of 2 h in the presence of actinomycin D. The stability of poly(A)-containing RNA in stimulated lymphocytes from normal donors is therefore not simply a manifestation of cell proliferation. In normal resting lymphocytes, Berger and Copper [(1975) Proc. Natl. Acad. Sci. U.S. 72, 3873--3877] reported the existence of 2 classes of polyadenylated mRNA with half-lives of under an hour and greater than 20 h, respectively. Since short-lived poly(A)-bearing mRNA is absent from mitogen-stimulated lymphocytes, the data suggest that stabilization of previously labile poly(A)-bearing RNA is one of many carefully regulated processes accompanying growth induction in normal lymphoid cells.

Publication types

  • Comparative Study

MeSH terms

  • Cell Cycle
  • Cytoplasm / metabolism
  • Dactinomycin / pharmacology
  • Deoxyadenosines / pharmacology
  • Humans
  • Lymphocytes / metabolism*
  • Phytohemagglutinins / pharmacology
  • Poly A / metabolism*
  • RNA / metabolism
  • RNA, Messenger / metabolism*
  • T-Lymphocytes / metabolism
  • Uridine / metabolism

Substances

  • Deoxyadenosines
  • Phytohemagglutinins
  • RNA, Messenger
  • Dactinomycin
  • Poly A
  • RNA
  • Uridine