Intracellular distribution of histone mRNAs in human fibroblasts studied by in situ hybridization

Journal Article · Fri Jan 01 04:00:00 EST 1988 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.85.2.463· OSTI ID:5317078

Lawrence, J B; Singer, R H; Villnave, C A; Stein, J L; Stein, G S

We have used in situ hybridization to study the intracellular distribution of mRNAs for cell cycle-dependent core and H1 histone proteins in human WI-38 fibroblasts. Because histones are abundant nuclear proteins and histone mRNA expression is tightly coupled to DNA synthesis, it was of interest to determine whether histone mRNAs are localized near the nucleus. Cells were hybridized with tritiated DNA probes specific for either histone H1, histone H4, actin, or poly(A)+ mRNA and were processed for autoradiography. In exponentially growing cultures, the fraction of histone mRNA-positive cells correlated well with the fraction of cells in S phase and was eliminated by hydroxyurea inhibition of DNA synthesis. Within individual cells the label for histone mRNA was widely distributed throughout the cytoplasm and did not appear to be more heavily concentrated near the nucleus. However, histone mRNA appeared to exhibit patchy, nonhomogeneous localization, and a quantitative evaluation confirmed that grain distributions were not as uniform as they were after hybridizations to poly(A)+ mRNA. Actin mRNA in WI-38 cells was also widely distributed throughout the cytoplasm but differed from histone mRNA in that label for actin mRNA was frequently most dense at the outermost region of narrow cell extensions. The localization of actin mRNA was less pronounced but qualitatively very similar to that previously described for chicken embryonic myoblasts and fibroblasts. We conclude that localization of histones in WI-38 cells is not facilitated by localization of histone protein synthesis near the nucleus and that there are subtle but discrete and potentially functional differences in the distributions of histone, actin, and poly(A)+ mRNAs.

• Research Organization: Univ. of Massachusetts Medical School, Worcester (USA)
• OSTI ID: 5317078
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Journal Name: Proc. Natl. Acad. Sci. U.S.A.; (United States) Vol. 85:2; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACTIN
ANIMAL CELLS
ANIMALS
AUTORADIOGRAPHY
AZINES
BIOLOGICAL LOCALIZATION
CELL CONSTITUENTS
CELL NUCLEI
CONNECTIVE TISSUE CELLS
CYTOPLASM
DISTRIBUTION
DNA REPLICATION
FIBROBLASTS
HETEROCYCLIC COMPOUNDS
HISTONES
HYBRIDIZATION
LABELLED COMPOUNDS
MAMMALS
MAN
MESSENGER-RNA
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
NUCLEOPROTEINS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PRIMATES
PROTEINS
PYRIMIDINES
RIBOSIDES
RNA
SOMATIC CELLS
SUBCELLULAR DISTRIBUTION
THYMIDINE
TRITIUM COMPOUNDS
VERTEBRATES