A transcriptionally active copia-like retroelement in Citrus limon.
The plant nuclear genome is largely composed of mobile DNA, which can rearrange genomes and other individual gene structure and also affect gene regulation through various promoted activities: transposition, insertion, excision, chromosome breakage, and ectopic recombination. Ty1-copia-like retrotransposon is a widespread class of transposable elements in the plant kingdom, representing a large part of the total DNA content. Here, a novel retrotransposon-like sequence was isolated and identified as the Ty1-copia-like reverse transcriptase domain (named here CLCoy1), based on the homology of known elements. Fluorescence in situ hybridization, revealed that CLCoy1 was mainly located in telomeric and sub-telomeric regions along the Citrus chromosomes. CLCoy1 composes 3.6% of the genome and, interestingly, while transposons are mostly specific to a species, this element was identified in other Citrus species such as Citrus aurantium, Fortunella margarita and Citrus paradisi, but undetected in Poncirus trifoliata. We also determined that wounding, salt and cell culture stress produced transcriptional activation of this novel retroelement in Citrus limon. The novel Ty1-copia-like element CLCoy1 may have played a major role in shaping genome structure and size during Citrus species evolution.
De Felice
Bruna
B
Department of Life Sciences, University of Naples II, Via Vivaldi 43, 81100 Caserta, Italy. bruna.defelice@unina2.it
Wilson
Robert R
RR
Argenziano
Carolina
C
Kafantaris
Ioanis
I
Conicella
Clara
C
D000595:Amino Acid Sequence; D002957:Citrus / Q000235:genetics*; D008969:Molecular Sequence Data; D012194:RNA-Directed DNA Polymerase / Q000737:chemistry / Q000235:genetics; D018626:Retroelements; D016415:Sequence Alignment; D014158:Transcription, Genetic
D018626:Retroelements; D012194:RNA-Directed DNA Polymerase