About 90 members of a major tandemly repeated DNA sequence family originally described in rye as pSc119.2 have been isolated from 11 diploid and polyploid Triticeae species using primers from along the length of the sequence for PCR amplification. Alignment and similarity analysis showed that the 120-bp repeat unit family is diverse with single nucleotide changes and few insertions and deletions occurring throughout the sequence, with no characteristic genome or species-specific variants having developed during evolution of the extant genomes. Fluorescent in situ hybridization showed that each of the large blocks of the repeat at chromosomal sites harboured many variants of the 120-bp repeat. There were substantial copy number differences between genomes, with abundant sub-terminal sites in rye, interstitial sites in the B genome of wheat, and relatively few sites in the A and D genome. We conclude that sequence homogenization events have not been operative in this repeat and that the common ancestor of the Triticeae tribe had multiple sequences of the 120-bp repeat with a range of variation not unlike that seen within and between species today. This diversity has been maintained when sites are moved within the genome and in all species since their divergence within the Triticeae.   

Anamthawat-Jónsson K, Heslop-Harrison JS: Isolation and characterization of genome-specific DNA sequences in Triticeae species. Mol Gen Genet 240:151–158 (1993).
Ashikawa I, Kurata N, Nagamura Y, Minobe Y: Cloning and mapping of telomere-associated sequences from rice. DNA Res 1:67–76 (1994).
Bedbrook JR, Jones J, O’Dell M, Thompson RD, Flavell RB: A molecular description of telomeric heterochromatin in Secale species. Cell 19:545–560 (1980).
Bennett MD, Smith JB: Nuclear DNA amounts in Angiosperms. Phil Trans R Soc London Ser B 334:309–345 (1991).
Burr B, Burr FA, Matz EC, Romero-Severson J: Pinning down loose ends: mapping telomeres and factors affecting their length. Plant Cell 4:953–960 (1992).
Castilho A, Heslop-Harrison JS: Physical mapping of 5S and 18S-25S rDNA and repetitive DNA sequences in Aegilops umbellulata. Genome 38:91–96 (1995).
Chen CM, Wang CT, Wang CJ, Ho CH, Kao YY, Chen CC: Two tandemly repeated telomere-associated sequences in Nicotiana plumbaginifolia. Chromosome Res 5:561–568 (1997).
Cuadrado A, Jouve N: Mapping and organization of highly-repeated DNA sequences by means of simultaneous and sequential FISH and C-banding in 6x-triticale. Chromosome Res 2:331–338 (1994).
Cuadrado A, Schwarzacher T: The chromosomal organization of simple sequence repeats in wheat and rye genomes. Chromosoma 107:587–594 (1998).
Cuadrado A, Ceoloni C, Jouve N: Variation in highly repetitive DNA composition of heterochromatin in rye studied by fluorescence in situ hybridization. Genome 38:1061–1069 (1995).
Dechyeva D, Gindullis F, Schmidt T: Divergence of satellite DNA and interspersion of dispersed repeats in the genome of the wild beet Beta procumbens. Chromosome Res 11:3–21 (2003).
Fajkus J, Kovarik A, Kralovics R, Bezdek M: Organization of telomeric and subtelomeric chromatin in the higher plant Nicotiana tabacum. Mol Gen Genet 247:633–638 (1995a).
Fajkus J, Kralovics R, Kovarik A, Fajkusova L: The telomeric sequence is directly attached to the HRS60 subtelomeric tandem repeat in tobacco chromosomes. FEBS Lett 364:33–35 (1995b).
Flavell RB: Repetitive DNA and chromosome evolution in plants. Philos Trans R Soc Lond B Biol Sci 312:227–242 (1986).
Flavell RB, Bennett MD, Smith JB, Smith DB: Genome size and the proportion of repeated nucleotide sequence DNA in plants. Biochem Genet 12:257–269 (1974).
Ganal MW, Lapitan NL, Tanksley SD: Macrostructure of the tomato telomeres. Plant Cell 3:87–94 (1991).
Ganal MW, Broun P, Tanksley SD: Genetic mapping of tandemly repeated telomeric DNA sequences in tomato (Lycopersicon esculentum). Genomics 14:444–448 (1992).
Gawel NJ, Jarret RL: A modified CTAB DNA extraction procedure for Musa and Ipomoea. Plant Molec Biol Rep 9:262–266 (1991).
Gerlach WL, Dyer TA: Sequence organization of the repeating units in the nucleus of wheat which contain 5S rRNA genes. Nucleic Acids Res 8:4851–4865 (1980).
Grebenstein B, Grebenstein O, Sauer W, Hemleben V: Distribution and complex organization of satellite DNA sequences in Aveneae species. Genome 39:1045–1050 (1996).
Heslop-Harrison JS: Comparative genome organization in plants: from sequence and markers to chromatin and chromosomes. Plant Cell 12:617–636 (2000).
Heslop-Harrison JS, Brandes A, Schwarzacher T: Tandemly repeated DNA sequences and centromeric chromosomal regions of Arabidopsis species. Chromosome Res 11:241–253 (2003).
Katsiotis A, Hagidimitriou M, Heslop-Harrison JS: The close relationship between the A and B genomes in Avena L. (Poaceae) determined by molecular cytogenetic analysis of total genomic, tandemly and dispersed repetitive DNA. Ann Bot 79:103–107 (1997).
Kilian A, Kleinhofs A: Cloning and mapping of telomere-associated sequences from Hordeum vulgare L. Mol Gen Genet 235:153–156 (1992).
Kishii M, Tsujimoto H: Genus-specific localization of the TaiI family of tandem-repetitive sequences in either the centromeric or subtelomeric regions in Triticeae species (Poaceae) and its evolution in wheat. Genome 45:946–955 (2002).
Kishii M, Nagaki K, Tsujimoto H, Sasakuma T: Exclusive localization of tandem repetitive sequences in subtelomeric heterochromatin regions of Leymus racemosus (Poaceae, Triticeae). Chromosome Res 7:519–529 (1999).
Kishii M, Nagaki K, Tsujimoto H: A tandem repetitive sequence located in the centromeric region of common wheat (Triticum aestivum) chromosomes. Chromosome Res 9:417–428 (2001).
Mao L, Devos KM, Zhu L, Gale MD: Cloning and genetic mapping of wheat telomere-associated sequences. Mol Gen Genet 254:584–591 (1997).
McIntyre CL, Pereira S, Moran LB, Appels R: New Secale cereale (rye) DNA derivatives for the detection of rye chromosome segments in wheat. Genome 33:635–640 (1990).
Mukai Y, Nakara Y, Yamamoto M: Simultaneous discrimination of three genomes in hexaploid wheat by multicolor fluorescence in situ hybridization using total genomic and highly repetitive DNA probes. Genome 36:489–494 (1993).
Nagaki K, Tsujimoto H, Isono K, Sasakuma T: Molecular characterization of a tandem repeat, Afa family, and its distribution among Triticeae. Theor Appl Genet 38:479–486 (1995).
Nagaki K, Tsujimoto H, Sasakuma T: Dynamics of tandem repetitive Afa-family sequences in Triticeae, wheat-related species. J Mol Evol 47:183–189 (1998).
Rayburn AL, Gill BS: Isolation of a D-genome specific repeated DNA sequence from Aegilops squarrosa. Plant Molec Biol Rep 4:102–109 (1986).
Schwarzacher T, Heslop-Harrison JS: Practical in situ Hybridization (Bios, Oxford 2000).
Swanson CP, Webster PL: The Cell, 4th ed (Prentice-Hall, Englewood Cliffs 1975).
Taketa S, Ando H, Takeda K, Harrison GE, Heslop-Harrison JS: The distribution, organization and evolution of two abundant and widespread repetitive DNA sequences in the genus Hordeum. Theor Appl Genet 100:169–176 (2000).
Vershinin AV, Heslop-Harrison JS: Comparative analysis of the nucleosomal structure of rye, wheat and their relatives. Plant Mol Biol 36:149–161 (1998).
Vershinin A, Svitashev S, Gummesson PO, Salomon B, von Bothmer R, Bryngelsson T: Characterization of a family of tandemly repeated DNA sequence in Triticeae. Theor Appl Genet 89:217–225 (1994).
Vershinin AV, Schwarzacher T, Heslop-Harrison JS: The large-scale genomic organization of repetitive DNA families at the telomeres of rye chromosomes. Plant Cell 7:1823–1833 (1995).
Wu T, Wang Y, Wu R: Transcribed repetitive DNA sequences in telomeric regions of rice (Oryza sativa). Plant Mol Biol 26:363–375 (1994).
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.