Format

Send to

Choose Destination
BMC Genomics. 2011 Nov 23;12:573. doi: 10.1186/1471-2164-12-573.

Transcriptional analysis of the HeT-A retrotransposon in mutant and wild type stocks reveals high sequence variability at Drosophila telomeres and other unusual features.

Author information

1
Institute of Evolutionary Biology (CSIC-UPF), Passeig Marítim de la Barceloneta 37-49, 08003, Barcelona, Spain.

Abstract

BACKGROUND:

Telomere replication in Drosophila depends on the transposition of a domesticated retroelement, the HeT-A retrotransposon. The sequence of the HeT-A retrotransposon changes rapidly resulting in differentiated subfamilies. This pattern of sequence change contrasts with the essential function with which the HeT-A is entrusted and brings about questions concerning the extent of sequence variability, the telomere contribution of different subfamilies, and whether wild type and mutant Drosophila stocks show different HeT-A scenarios.

RESULTS:

A detailed study on the variability of HeT-A reveals that both the level of variability and the number of subfamilies are higher than previously reported. Comparisons between GIII, a strain with longer telomeres, and its parental strain Oregon-R indicate that both strains have the same set of HeT-A subfamilies. Finally, the presence of a highly conserved splicing pattern only in its antisense transcripts indicates a putative regulatory, functional or structural role for the HeT-A RNA. Interestingly, our results also suggest that most HeT-A copies are actively expressed regardless of which telomere and where in the telomere they are located.

CONCLUSIONS:

Our study demonstrates how the HeT-A sequence changes much faster than previously reported resulting in at least nine different subfamilies most of which could actively contribute to telomere extension in Drosophila. Interestingly, the only significant difference observed between Oregon-R and GIII resides in the nature and proportion of the antisense transcripts, suggesting a possible mechanism that would in part explain the longer telomeres of the GIII stock.

PMID:
22111838
PMCID:
PMC3235214
DOI:
10.1186/1471-2164-12-573
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center