Extreme Structural Heterogeneity Among the Members of a Maize Retrotransposon Family

Corresponding author: Susan R. Wessler, Department of Genetics, University of Georgia, Athens, GA 30602., sue{at}dogwood.botany.uga.edu (E-mail).

Communicating editor: V. SUNDARESAN

A few families of retrotransposons characterized by the presence of long terminal repeats (LTRs) have amplified relatively recently in maize and account for >50% of the genome. Surprisingly, none of these elements have been shown to cause a single mutation. In contrast, most of the retrotransposon-induced mutations isolated in maize are caused by the insertion of elements that are present in the genome at 2–50 copies. To begin to understand what limits the amplification of this mutagenic class of LTR-retrotransposons, we are focusing on five elements previously identified among 17 mutations of the maize waxy gene. One of these elements, Stonor, has sustained a deletion of the entire gag region and part of the protease domain. Missing sequences were recovered from larger members of the Stonor family and indicate that the deletion probably occurred during retrotransposition. These large elements have an exceptionally long leader of 2 kb that includes a highly variable region of ~1 kb that has not been seen in previously characterized retrotransposons. This region serves to distinguish each member of the Stonor family and indicates that no single element has yet evolved that can attain the very high copy numbers characteristic of other element families in maize.

This article has been cited by other articles:

				M. Tomita, K. Shinohara, and M. Morimoto Revolver is a New Class of Transposon-like Gene Composing the Triticeae Genome DNA Res, February 1, 2008; 15(1): 49 - 62. [Abstract] [Full Text] [PDF]

				R. Jing, M. R. Knox, J. M. Lee, A. V. Vershinin, M. Ambrose, T. H. N. Ellis, and A. J. Flavell Insertional Polymorphism and Antiquity of PDR1 Retrotransposon Insertions in Pisum Species Genetics, October 1, 2005; 171(2): 741 - 752. [Abstract] [Full Text] [PDF]

				G. Tapia, I. Verdugo, M. Yanez, I. Ahumada, C. Theoduloz, C. Cordero, F. Poblete, E. Gonzalez, and S. Ruiz-Lara Involvement of Ethylene in Stress-Induced Expression of the TLC1.1 Retrotransposon from Lycopersicon chilense Dun. Plant Physiology, August 1, 2005; 138(4): 2075 - 2086. [Abstract] [Full Text] [PDF]

				J. Ma, K. M. Devos, and J. L. Bennetzen Analyses of LTR-Retrotransposon Structures Reveal Recent and Rapid Genomic DNA Loss in Rice Genome Res., May 1, 2004; 14(5): 860 - 869. [Abstract] [Full Text] [PDF]

				L. Alonso-Gonzalez, A. Dominguez, and J. Albornoz Structural Heterogeneity and Genomic Distribution of Drosophila melanogaster LTR-Retrotransposons Mol. Biol. Evol., March 1, 2003; 20(3): 401 - 409. [Abstract] [Full Text] [PDF]

				K. M. Devos, J. K.M. Brown, and J. L. Bennetzen Genome Size Reduction through Illegitimate Recombination Counteracts Genome Expansion in Arabidopsis Genome Res., July 1, 2002; 12(7): 1075 - 1079. [Abstract] [Full Text] [PDF]

				N. Jiang, Z. Bao, S. Temnykh, Z. Cheng, J. Jiang, R. A. Wing, S. R. McCouch, and S. R. Wessler Dasheng: A Recently Amplified Nonautonomous Long Terminal Repeat Element That Is a Major Component of Pericentromeric Regions in Rice Genetics, July 1, 2002; 161(3): 1293 - 1305. [Abstract] [Full Text] [PDF]

				Y. Kimura, Y. Tosa, S. Shimada, R. Sogo, M. Kusaba, T. Sunaga, S. Betsuyaku, Y. Eto, H. Nakayashiki, and S. Mayama OARE-1, a Ty1-copia Retrotransposon in Oat Activated by Abiotic and Biotic Stresses Plant Cell Physiol., December 1, 2001; 42(12): 1345 - 1354. [Abstract] [Full Text] [PDF]

				N. Elrouby and T. E. Bureau A Novel Hybrid Open Reading Frame Formed by Multiple Cellular Gene Transductions by a Plant Long Terminal Repeat Retroelement J. Biol. Chem., November 2, 2001; 276(45): 41963 - 41968. [Abstract] [Full Text] [PDF]

				X. Zhang, C. Feschotte, Q. Zhang, N. Jiang, W. B. Eggleston, and S. R. Wessler P instability factor: An active maize transposon system associated with the amplification of Tourist-like MITEs and a new superfamily of transposases PNAS, September 26, 2001; (2001) 211442198. [Abstract] [Full Text] [PDF]

				T. Beguiristain, M.-A. Grandbastien, P. Puigdomenech, and J. M. Casacuberta Three Tnt1 Subfamilies Show Different Stress-Associated Patterns of Expression in Tobacco. Consequences for Retrotransposon Control and Evolution in Plants Plant Physiology, September 1, 2001; 127(1): 212 - 221. [Abstract] [Full Text] [PDF]

				L. J. Gahan, F. Gould, and D. G. Heckel Identification of a Gene Associated with Bt Resistance in Heliothis virescens Science, August 3, 2001; 293(5531): 857 - 860. [Abstract] [Full Text] [PDF]

				T. Langdon, C. Seago, M. Mende, M. Leggett, H. Thomas, J. W. Forster, H. Thomas, R. N. Jones, and G. Jenkins Retrotransposon Evolution in Diverse Plant Genomes Genetics, September 1, 2000; 156(1): 313 - 325. [Abstract] [Full Text]

				X. Zhang, C. Feschotte, Q. Zhang, N. Jiang, W. B. Eggleston, and S. R. Wessler From the Cover: P instability factor: An active maize transposon system associated with the amplification of Tourist-like MITEs and a new superfamily of transposases PNAS, October 23, 2001; 98(22): 12572 - 12577. [Abstract] [Full Text] [PDF]

				B. C. Meyers, S. V. Tingey, and M. Morgante Abundance, Distribution, and Transcriptional Activity of Repetitive Elements in the Maize Genome Genome Res., October 1, 2001; 11(10): 1660 - 1676. [Abstract] [Full Text] [PDF]