Please use this identifier to cite or link to this item: http://hdl.handle.net/2445/7382
Title: The non-LTR retrotransposons in Ciona intestinalis: new insights into the evolution of chordate genomes
Author: Permanyer i Ugartemendia, Jon
Gonzàlez-Duarte, Roser
Albalat Rodríguez, Ricard
Keywords: Genètica molecular
Genètica animal
Cordats
Evolution
Molecular biology
Genome studies
Issue Date: 2003
Publisher: BioMed Central
Abstract: Background: Non-long terminal repeat (non-LTR) retrotransposons have contributed to shaping the structure and function of genomes. In silico and experimental approaches have been used to identify the non-LTR elements of the urochordate Ciona intestinalis. Knowledge of the types and abundance of non-LTR elements in urochordates is a key step in understanding their contribution to the structure and function of vertebrate genomes. Results: Consensus elements phylogenetically related to the I, LINE1, LINE2, LOA and R2 elements of the 14 eukaryotic non-LTR clades are described from C. intestinalis. The ascidian elements showed conservation of both the reverse transcriptase coding sequence and the overall structural organization seen in each clade. The apurinic/apyrimidinic endonuclease and nucleic-acid-binding domains encoded upstream of the reverse transcriptase, and the RNase H and the restriction enzyme-like endonuclease motifs encoded downstream of the reverse transcriptase were identified in the corresponding Ciona families. Conclusions: The genome of C. intestinalis harbors representatives of at least five clades of non-LTR retrotransposons. The copy number per haploid genome of each element is low, less than 100, far below the values reported for vertebrate counterparts but within the range for protostomes. Genomic and sequence analysis shows that the ascidian non-LTR elements are unmethylated and flanked by genomic segments with a gene density lower than average for the genome. The analysis provides valuable data for understanding the evolution of early chordate genomes and enlarges the view on the distribution of the non-LTR retrotransposons in eukaryotes.
Note: Reproducció del document publicat a http://dx.doi.org/10.1186/gb-2003-4-11-r73
It is part of: Genome Biology, 2003, vol. 4, núm. 73
URI: http://hdl.handle.net/2445/7382
ISSN: 1465-6914
Appears in Collections:Articles publicats en revistes (Genètica, Microbiologia i Estadística)

Files in This Item:
File Description SizeFormat 
520455.pdf556.08 kBAdobe PDFView/Open


This item is licensed under a Creative Commons License Creative Commons