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S R Haynes

Publications and source records attributed to S R Haynes.

41 records · Page 3Linked to original sources

Discrete and heterogeneous high molecular weight RNAs complementary to a long dispersed repeat family (a possible transposon) of human DNA.

Approximately 1% of heterogeneous nuclear RNA and approximately 0.035% of cytoplasmic RNA from a cultured line of human lymphoblastoid cells is complementary to a long dispersed repetitious sequence that comprises at least 6% of human DNA. The complementary nuclear RNA is both heterogeneously and discretely sized and is present in both poly(A)-terminated and non-poly(A)-terminated molecules. The complementary cytoplasmic RNA is mainly in discretely sized molecules ranging in size from approximately 600 to 8200 bases, some of which are most abundantly represented in poly(A)-terminated molecules, whereas others are most abundantly represented in non-poly(A)-terminated molecules. Few, if any, of the complementary cytoplasmic RNAs can be found associated with polyribosomes. The dispersed repeat sequence exhibits substantial restriction enzyme fragment length polymorphisms in human DNA and is also present in mouse DNA, although some regions of the human repeat appear to be more abundantly represented in mouse DNA than are other regions.

Animals↗

Kpn I family of long-dispersed repeated DNA sequences of man: evidence for entry into genomic DNA of DNA copies of poly(A)-terminated Kpn I RNAs.

We have isolated eight cDNA clones complementary to the human Kpn I repeat and determined the base sequence of three. We have also determined a portion of the base sequences of three human Kpn I family members. The three cDNA sequences are extensively homologous with the 3' ends of the three genomic Kpn I family members and with a simian Kpn I family member recently described [Thayer, R. E. & Singer, M. F. (1983) Mol. Cell. Biol. 6, 967-973]. The genomic repeats terminate in regions of sequence rich in dAMP residues close to sequences at the 3' ends of the cDNA clones; a precise 3'-terminal nucleotide cannot be distinguished. These structural features are consistent with the dispersal of at least some Kpn I family members by entry into genomic DNA of copies of Kpn I RNA transcripts. Each cDNA contains a long poly(dAMP) homopolymer at its 3' end and either one or two A-A-T-A-A-A polyadenylylation signal sequences upstream from it, suggesting that Kpn I family members may be transcribed by RNA polymerase II.

Base Sequence↗

Low molecular weight RNAs transcribed in vitro by RNA polymerase III from Alu-type dispersed repeats in Chinese hamster DNA are also found in vivo.

An Alu-type dispersed repeat previously identified in a cloned fragment of Chinese hamster DNA [Haynes, S. R., Toomey, T. P., Leinwand, L. & Jelinek, W. R. (1981) Mol. Cell. Biol. 1, 573-583] serves as a template for cell-free transcription of discrete low molecular weight RNAs by RNA polymerase III [RNA nucleotidyltransferase (DNA-directed), EC 2.7.7.6]. A class of analogous RNAs has been isolated from growing Chinese hamster cells by hybridization of total low molecular weight nuclear RNAs to the cloned DNA fragment from which cell-free transcription occurs. Two-dimensional analysis of RNase digestion products of these RNAs suggests that they are transcribed from multiple members of the Alu-type dispersed repeat family.

Animals↗

The Chinese hamster Alu-equivalent sequence: a conserved highly repetitious, interspersed deoxyribonucleic acid sequence in mammals has a structure suggestive of a transposable element.

A consensus sequence has been determined for a major interspersed deoxyribonucleic acid repeat in the genome of Chinese hamster ovary cells (CHO cells). This sequence is extensively homologous to (i) the human Alu sequence (P. L. Deininger et al., J. Mol. Biol., in press), (ii) the mouse B1 interspersed repetitious sequence (Krayev et al., Nucleic Acids Res. 8:1201-1215, 1980) (iii) an interspersed repetitious sequence from African green monkey deoxyribonucleic acid (Dhruva et al., Proc. Natl. Acad. Sci. U.S.A. 77:4514-4518, 1980) and (iv) the CHO and mouse 4.5S ribonucleic acid (this report; F. Harada and N. Kato, Nucleic Acids Res. 8:1273-1285, 1980). Because the CHO consensus sequence shows significant homology to the human Alu sequence it is termed the CHO Alu-equivalent sequence. A conserved structure surrounding CHO Alu-equivalent family members can be recognized. It is similar to that surrounding the human Alu and the mouse B1 sequences, and is represented as follows: direct repeat-CHO-Alu-A-rich sequence-direct repeat. A composite interspersed repetitious sequence has been identified. Its structure is represented as follows: direct repeat-residue 47 to 107 of CHO-Alu-non-Alu repetitious sequence-A-rich sequence-direct repeat. Because the Alu flanking sequences resemble those that flank known transposable elements, we think it likely that the Alu sequence dispersed throughout the mammalian genome by transposition.

Animals↗