Protein synthesis in differentiating normal and leukemic erythroid cells

Abstract

Erythroleukemic cells transformed by the AEV or S13 strains of avian erythroblastosis virus differentiate in vitro either spontaneously (S13) or following a temperature induction (temperature-sensitive mutants of AEV). To study differentiation in these cells at the molecular level, homogeneous fractions of maturing cells at discrete stages of differentiation were prepared by Percoll density-gradient centrifugation. This method was also used for the fractionation of differentiating normal erythroid cells separated from total bone marrow by an immunological "panning" technique. Total protein synthesis in these cells was then analyzed by two-dimensional gel electrophoresis. The expression of several proteins was altered in differentiating leukemic cells but not in their normal counterparts. However, in general, the normal and leukemic cells from comparable stages of maturity showed closely related protein synthetic patterns. Similar early and late changes in the synthesis of a number of polypeptides were detected during maturation from early erythroid precursors to terminally differentiated erythrocytes. Further, the leukemic as well as the normal cells appeared to undergo a major switch in total protein synthetic pattern during late differentiation. These results demonstrate that normal and erythroleukemic cells differentiate along similar pathways.

Autocrine growth induced by kinase type oncogenes in myeloid cells requires AP-1 and NF-M, a myeloid specific, C/EBP-like factor.

“…Cell lines HD3: AEV transformed erythroblasts expressing the viral erbA and erbB oncogenes (Adkins et al, 1985); HD1 1: MC29 transformed macrophages expressing the v-myc oncogene ; MSB-I: T-lymphoid cell line MDCC-MSB-1; RPL-12: B-lymphoid cell line LVSCC-TLT; REV-NPB4: preB/preT lymphoblasts expressing v-rel (Beug et al, 1981); BM-2: AMV transformed monoblasts expressing v-myb (Moscovici et al, 1982); HD57: E26 (v-gag-myb-ets) transformed immature multipotent cell line (T. Graf, in preparation).…”

Co‐operation between viral oncogenes in avian erythroid and myeloid leukaemia

“…The ability of v-mil to induce production of cMGF is shared with a whole series of cytoplasmic oncogenes, such as the tyrosine kinase oncogenes v-src, v-erb B, ufps, v-yes and v-ras ( [18,30] and I. Stanley, A. Leutz & T. Graf, unpublished). Some of these oncogenes induce a more differentiated phenotype in myc-transformed macrophages and myb-transformed myeloblasts ( [12] and T. Graf & H. Beug, unpublished).…”

Identification and characterization of the chicken transferrin receptor

“…We have been studying chick erythroid differentiation, in particular cell-surface molecules whose regulation is altered during terminal differentiation, induced in vitro, of erythroblasts transformed by temperature-sensitive mutants of avian-erythroblastosis virus (ts AEV) (Beug et al, 1982;Hayman et al, 1982;Adkins et al, 1985). Because of its known role in erythropoiesis and cell proliferation in mammalian cells, we reasoned that the chicken transferrin receptor may be playing an important role in the differentiation of chicken erythroblasts to red blood cells.…”