Summary
Southern blot hybridizations were performed to investigate the ribosomal DNA structure inAllium cepa (Liliaceae). The analysis of single and double digestions with Eco RI, Hind III, and Bam HI endonuclease restriction enzymes showed the presence of at least two types of repetitive units. The gene types were present in each single individual ofAllium cepa analyzed, notwithstanding the variation of the ribosomal gene number from 5,500 to 11,900 and the NOR number from 2 to 4. The first and the second gene type are 12.7 kb long and the first type is much more represented inAllium cepa genome. The differences between the two gene types consist in the position of the Hind III restriction sites in the external spacer.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Appels, R., Gerlach, W. L., Dennis, E. S., Swift, H., Peacock, W. J., 1980: Molecular and chromosomal organization of DNA sequences coding for the ribosomal RNAs in cereals. Chromosoma (Berl.)78, 293–311.
Barnett, T., Rae, P. M. M., 1979: A. 9.6 kb intervening sequence in D. virilis, and sequence homology in rDNA interruptions of diverse species ofDrosophila and other Diptera. Cell16, 763–775.
Battaglia, E., Maggini, F., 1968: The use of osmium for staining the nucleolus in squash technique. Caryologia21, 287–292.
Buongiorno-Nardelli, M., Amaldi, F., Beccari, E., Junakovic, N., 1977: Size of ribosomal DNA repeating units inXenopus laevis: limited individual heterogeneity and extensive population polymorphism. J. molec. Biol.110, 105–117.
Cammarano, P., Pons, S., Londei, P., 1975: Discontinuity of the large ribosomal subunit RNA and rRNA molecular weights in eukaryote evolution. Acta biol. med. germ.34, 1123–1135.
Cory, S., Adams, J. M., 1977: A very large repeating unit of mouse DNA containing the 18 S, 28 S, and 5.8 S rRNA genes. Cell11, 795–805.
Commerford, S. L., 1971: Iodination of nucleic acidin vitro. Biochemistry10, 1993–2000.
Delseny, M., Aspart, L., Cooke, R., Grellet, F., Penon, P., 1979: Restriction analysis of radish nuclear genes coding for rRNA: evidence for heterogeneity. Biochem. biophys. Res. Commun.91, 540–547.
Friedrich, H., Hemleben, V., Meagher, R. B., Key, J. L., 1979: Purification and restriction endonuclease mapping of soybean 18 S and 25 S ribosomal RNA genes. Planta146, 467–473.
Gerlach, W. L., Bedbrook, J. R., 1979: Cloning and characterization of ribosomal RNA genes from wheat and barley. Nucleic Acid Res.7, 1869–1885.
Gillespie, D., Spiegelman, S., 1965: A quantitative assay for DNA/RNA hybrids with DNA immobilized on a membrane. J. molec. Biol.12, 829–842.
Glover, D. M., Hogness, D. S., 1977: A novel arrangement of the 18 S and 25 S sequences in a repeating unit forDrosophila melanogaster rDNA. Cell10, 167–176.
Ingle, J., Timmis, J. N., Sinclair, J., 1975: The relationship between satellite DNA, ribosomal RNA gene redundancy, and genome size in plants. Plant Physiol.55, 496–501.
Maggini, F., Barsanti, P., Marazia, T., 1978: Individual variation of the nucleolus organizer regions inAllium cepa andA. sativum. Chromosoma (Berl.)66, 173–183.
Maizels, N., 1976: Dictyostelium 17 S, 25 S, and 5 S rDNAs lie within a 38,000 base pairs repeated unit. Cell9, 431–438.
Oono, F., Sugiura, M., 1980: Heterogeneity of the ribosomal RNA gene clusters in rice. Chromosoma (Berl.)76, 85–89.
Pellegrini, M., Manning, J., Davidson, N., 1977: Sequence arrangement of the rDNA ofDrosophila melanogaster. Cell10, 213–224.
Renkawitz, R., Gerbi, S. A., Glätzer, K. H., 1979: Ribosomal DNA ofSclara coprophila has a very small homogeneous repeat unit. Molec. gen. Genet.1973, 1–13.
Ritossa, F., Spiegelman, S., 1965: Localization of the DNA complementary to ribosomal RNA in the nucleolus organizing regions ofDrosophila melanogaster. Proc. nat. Acad. Sci. (Wash.)53, 737–745.
Scott, N. S., Ingle, J., 1973: The genes for cytoplasmic ribosomal ribonucleic acid in higher plants. Plant Physiol.51, 677–684.
Southern, E. M., 1975: Detection of specific sequence among DNA fragments separated by gel electrophoresis. J. molec. Biol.98, 503–517.
Varsanyi-Breiner, A., Gusella, J. F., Keys, C., Housman, D. E., Sullivan, D., Brisson, N., Verma, D. P. S., 1980: The organization of a nuclear DNA sequence from a higher plant: molecular cloning and characterization of soybean ribosomal DNA. Gene7, 317–334.
Wellauer, P. K., Dawid, I. B., Brown, D. D., Reeder, R. H., 1976: The molecular basis of length heterogeneity in ribosomal DNA fromXenopus laevis. J. molec. Biol.105, 461–486.
— —, 1977: The structural organization of ribosomal DNA inDrosophila melanogaster. Cell10, 193–212.
White, R. L., Hogness, 1977: R-loop mapping of the 18 S and 28 S sequences in the long and short repeating units ofDrosophila melanogaster rDNA. Cell10, 177–192.
Author information
Authors and Affiliations
Additional information
Work supported by CNR contract no. 74/0267.
Rights and permissions
About this article
Cite this article
Maggini, F., Carmona, M.J. Sequence heterogeneity of the ribosomal DNA inAllium cepa (Liliaceae). Protoplasma 108, 163–171 (1981). https://doi.org/10.1007/BF01276890
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01276890