novel gene is transcribed in the chicken alpha-globin gene domain in the direction opposite to the globin genes

• Published in: Molecular & general genetics Vol. 262; no. 6; pp. 1012 - 1021
• Main Authors: Sjakste, N, Iarovaia, O.V, Razin, S.V, Linares-Cruz, G, Sjakste, T, Le Gac, V, Zhao, Z, Scherrer, K
• Format: Journal Article
• Language: English
• Published: Germany 2000
• Subjects: Animals; antisense transcription; Base Sequence; Cell Line; Cell Nucleus - metabolism; Chickens; Chromosome Mapping; Cytoplasm - metabolism; Exons; genbank/af098919; genes; ggprx gene; globins; Globins - genetics; Humans; in situ hybridization; messenger RNA; Mice; Molecular Sequence Data; Multigene Family; Northern blotting; nucleic acid hybridization; nucleotide sequences; precursors; restriction mapping; RNA Probes - genetics; RNA, Antisense - genetics; RNA, Antisense - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Homology, Nucleic Acid; Species Specificity; transcription (genetics); transcription units; Transcription, Genetic
• ISSN: 0026-8925; 1432-1874
• DOI: 10.1007/PL00008644

A novel gene transcribed in the direction opposite to that of the globin genes was found in the chicken alpha-globin gene domain. Northern hybridisation with single-stranded riboprobes revealed that a 4.5-kb poly(A)+ RNA is transcribed in antisense polarity with respect to the globin genes. The transcription unit encoding this RNA seems to overlap the entire cluster of alpha-globin genes and extends at least 15 kb upstream from pi, the first of the alpha-globin genes. This new transcript shows partial sequence homology with that encoded by the human "-14" gene. An oligonucleotide based on part of a restriction fragment of chicken DNA that is 80% homologous to exon 4 of the human "-14" gene hybridises with a 4.5-kb RNA molecule. In situ hybridisation of globin-antisense probes, that detect polyribosomal mRNAs of 1.7 and 2.5 kb on Northern blots, shows these "antisense" transcripts to be present in the cytoplasm. The 4.5-kb RNA is absent in polyribosomal poly(A)+ RNA and may, hence, represent a nuclear pre-mRNA transcribed from the chicken gene that is homologous to the human "-14" gene. The expression of this gene is not specific to erythroid cells; analogous transcripts were also detected in poly(A)+ RNA extracted from a chicken lymphoblastoma cell line (HP50). Taken together, these data allow us to postulate the existence in the chicken genome of a novel gene, for which we suggest the name "ggPRX" in analogy to the murine mProx1, a gene identified in the upstream region of the alpha-globin gene domain in mice.