Limits...
Evidence for co-evolution between human microRNAs and Alu-repeats.

Lehnert S, Van Loo P, Thilakarathne PJ, Marynen P, Verbeke G, Schuit FC - PLoS ONE (2009)

Bottom Line: The individual miRNA genes within this cluster are flanked by an Alu-LINE signature, which has been duplicated with the clustered miRNA genes.Gene duplication events in this locus are supported by comparing repeat length variations of the LINE elements within the cluster with those in the rest of the chromosome.Thus, a dual relationship exists between an evolutionary young miRNA cluster and their Alu targets that may have evolved in the same time window.

View Article: PubMed Central - PubMed

Affiliation: Gene Expression Unit, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium.

ABSTRACT
This paper connects Alu repeats, the most abundant repetitive elements in the human genome and microRNAs, small RNAs that alter gene expression at the post-transcriptional level. Base-pair complementarity could be demonstrated between the seed sequence of a subset of human microRNAs and Alu repeats that are integrated parallel (sense) in mRNAs. The most common target site coincides with the evolutionary most conserved part of Alu. A primate-specific gene cluster on chromosome 19 encodes the majority of miRNAs that target the most conserved sense Alu site. The individual miRNA genes within this cluster are flanked by an Alu-LINE signature, which has been duplicated with the clustered miRNA genes. Gene duplication events in this locus are supported by comparing repeat length variations of the LINE elements within the cluster with those in the rest of the chromosome. Thus, a dual relationship exists between an evolutionary young miRNA cluster and their Alu targets that may have evolved in the same time window. One hypothesis for this dual relationship is that these miRNAs could protect against too high rates of duplicative transposition, which would destroy the genome.

Show MeSH

Related in: MedlinePlus

Comparison of repeat content between miRNA clusters on Chr14 and Chr19.Panel A) shows the absolute number of repeats found in each cluster divided for SINE and LINE elements, subdivided by repeat family. The absolute number of the strand of integration (plus and minus strand) from SINE and LINE elements is shown in Panel B).
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2637760&req=5

pone-0004456-g003: Comparison of repeat content between miRNA clusters on Chr14 and Chr19.Panel A) shows the absolute number of repeats found in each cluster divided for SINE and LINE elements, subdivided by repeat family. The absolute number of the strand of integration (plus and minus strand) from SINE and LINE elements is shown in Panel B).

Mentions: We next analyzed the nature of the repeats in C19MC as these were recently proposed to be contributing to duplication events during evolution of the cluster [16]. As a control, we studied C14MC, the biggest known mammalian miRNA cluster which is on human chromosome 14 [22]. We found that these two clusters differ extensively in their repeat element composition. As shown in Figure 3, the repeat composition of C14MC approximated the expected situation of the whole genome, (equal amounts of LINE and SINE integrations on the plus and minus strand). The situation on C19MC was very different. For C19MC, a difference in repeat class content (∼90% SINE vs. ∼10% LINE) as well as in strand of integration was seen (∼80% SINE and 100% LINE minus Strand; Figure 3). Thus, a much more asymmetric SINE and LINE distribution was seen for C19MC than for C14MC. As is illustrated in Figure S4, (red arrow) this remarkable asymmetry of plus/minus strand distribution in the miRNA cluster also contrasts with another control, namely the rest of chromosome 19.


Evidence for co-evolution between human microRNAs and Alu-repeats.

Lehnert S, Van Loo P, Thilakarathne PJ, Marynen P, Verbeke G, Schuit FC - PLoS ONE (2009)

Comparison of repeat content between miRNA clusters on Chr14 and Chr19.Panel A) shows the absolute number of repeats found in each cluster divided for SINE and LINE elements, subdivided by repeat family. The absolute number of the strand of integration (plus and minus strand) from SINE and LINE elements is shown in Panel B).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2637760&req=5

pone-0004456-g003: Comparison of repeat content between miRNA clusters on Chr14 and Chr19.Panel A) shows the absolute number of repeats found in each cluster divided for SINE and LINE elements, subdivided by repeat family. The absolute number of the strand of integration (plus and minus strand) from SINE and LINE elements is shown in Panel B).
Mentions: We next analyzed the nature of the repeats in C19MC as these were recently proposed to be contributing to duplication events during evolution of the cluster [16]. As a control, we studied C14MC, the biggest known mammalian miRNA cluster which is on human chromosome 14 [22]. We found that these two clusters differ extensively in their repeat element composition. As shown in Figure 3, the repeat composition of C14MC approximated the expected situation of the whole genome, (equal amounts of LINE and SINE integrations on the plus and minus strand). The situation on C19MC was very different. For C19MC, a difference in repeat class content (∼90% SINE vs. ∼10% LINE) as well as in strand of integration was seen (∼80% SINE and 100% LINE minus Strand; Figure 3). Thus, a much more asymmetric SINE and LINE distribution was seen for C19MC than for C14MC. As is illustrated in Figure S4, (red arrow) this remarkable asymmetry of plus/minus strand distribution in the miRNA cluster also contrasts with another control, namely the rest of chromosome 19.

Bottom Line: The individual miRNA genes within this cluster are flanked by an Alu-LINE signature, which has been duplicated with the clustered miRNA genes.Gene duplication events in this locus are supported by comparing repeat length variations of the LINE elements within the cluster with those in the rest of the chromosome.Thus, a dual relationship exists between an evolutionary young miRNA cluster and their Alu targets that may have evolved in the same time window.

View Article: PubMed Central - PubMed

Affiliation: Gene Expression Unit, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium.

ABSTRACT
This paper connects Alu repeats, the most abundant repetitive elements in the human genome and microRNAs, small RNAs that alter gene expression at the post-transcriptional level. Base-pair complementarity could be demonstrated between the seed sequence of a subset of human microRNAs and Alu repeats that are integrated parallel (sense) in mRNAs. The most common target site coincides with the evolutionary most conserved part of Alu. A primate-specific gene cluster on chromosome 19 encodes the majority of miRNAs that target the most conserved sense Alu site. The individual miRNA genes within this cluster are flanked by an Alu-LINE signature, which has been duplicated with the clustered miRNA genes. Gene duplication events in this locus are supported by comparing repeat length variations of the LINE elements within the cluster with those in the rest of the chromosome. Thus, a dual relationship exists between an evolutionary young miRNA cluster and their Alu targets that may have evolved in the same time window. One hypothesis for this dual relationship is that these miRNAs could protect against too high rates of duplicative transposition, which would destroy the genome.

Show MeSH
Related in: MedlinePlus