In Chicken Leukemia Cells Globin Genes Are Fully Transcribed but Their RNAs Are Retained in the Perinucleolar Area

• Published in: Experimental cell research Vol. 270; no. 2; pp. 159 - 165
• Main Authors: Iarovaia, Olga, Razin, Sergey V., Linares-Cruz, Gustavo, Sjakste, Nikolajs, Scherrer, Klaus
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2001
• Subjects: Animals; Blotting, Northern; Cell Differentiation - physiology; Cell Division - physiology; Cell Nucleolus - genetics; Cell Nucleolus - metabolism; chicken nucleolus; Chickens; Cytoplasm - metabolism; erythroid cells; globin genes; Globins - genetics; Leukemia; pre-mRNA; RNA Precursors - analysis; RNA Precursors - metabolism; RNA processing; RNA, Messenger - analysis; RNA, Messenger - metabolism; Transcription, Genetic - physiology; Tumor Cells, Cultured; chicken nucleolus; pre-mRNA; erythroid cells; RNA processing; globin genes
• ISSN: 0014-4827; 1090-2422
• DOI: 10.1006/excr.2001.5332

Using hybridization in situ with a ribo-probe recognizing transcripts of the chicken alpha A globin gene, we show here that in proliferating AEV-transformed erythroblasts this gene is strongly transcribed, but the corresponding transcripts are retained in the nuclei. Most surprisingly, this globin RNA accumulates in the perinucleolar areas in a pattern never observed before. Upon induction of cells to differentiate, leading to productive expression of the hemoglobins, the transcripts of the alpha A globin gene were found for the most part in the cytoplasm. In the nuclei of differentiated cells, the globin RNA is concentrated in one or two specific spots, which are likely to represent the “processing centers” (PCs) of the globin RNA. The results presented indicate that posttranscriptional steps of regulation involving in particular the perinuclear areas are of major importance for erythroid differentiation.