GHRLOS, which gives rise to endogenous ghrelin natural antisense transcripts. exhibits features which are common to many non-coding RNA genes, including extensive splicing, lack of significant and conserved open reading frames, differential expression and lack of conservation in vertebrates.
GHRLOS:ghrelin opposite strand/antisense RNA(HGNC nomenclature)
"GHRL antisense RNA 1 (non-protein coding)", GHRL-AS1, NCRNA00068, "non-protein coding RNA 68"
GHRLOS transcripts that extend over 1.4 kb of the promoter region and 106 nucleotides of exon 4 of the ghrelin gene(GHRL) initiate 4.8 kb downstream of the terminal exon 4 of GHRL and are present in the 3' untranslated exon of the adjacent gene TATDN2 (TatD DNase domain containing 2). The 3' region of GHRLOS is also antisense, in a tail-to-tail fashion to a novel terminal exon of the neighbouring SEC13 gene, which is important inprotein transport. GHRLOS that is riddled with stop codons is little nucleotide and amino-acid sequence conservation between vertebrates. The gene spans 44 kb on 3p25.3, is extensively spliced and harbours multiple variable exons.
GHRLOS RNA transcripts display several distinctive features of non-coding (ncRNA) genes, including 5' capping, polyadenylation, extensive splicing and short open reading frames. GHRLOS natural antisense transcripts, functioning as a non-coding RNA,may regulate one or both of these genes, because GHRLOS overlaps the terminal exons of both GHRL andSEC13-T
We have also investigated the expression of GHRLOS and found evidence of differential tissue expression. It is highly expressed in tissues which are emerging as major sites of non-coding RNA expression (the thymus, brain, and testis), as well as in the ovary and uterus. In contrast, very low levels were found in the stomach where sense, GHRL derived RNAs are highly expressed. For non-quantitative RT-PCR analysis of GHRLOS splicing, RT-PCRs were performed with a forward primer in a region common to the 5' terminal exon Ia/b and a reverse primer in the 3' terminal exon 4 of GHRLOS.
To detect long, chimaeric transcripts, we employed RT-PCR with a forward primer in exon 2 of TATDN2(ChiOut-F) and a reverse primer in exon 1 of GHRLOS.
To allow strand-specific and RNA-specific amplification of GHRLOS transcripts, reverse transcription was performed using a gene-specific primer in exon 4 with a linker (LK) sequence attached to the 5' end of the primer.
To detect sense GHRL transcripts,a strand-specific RT-PCR approach was employed, with a reverse transcription primer spanning the 3' terminal exon 4 of the ghrelin gene (GHRLex4_RT_LK) followed by PCR with an exon 4 specific forward primer (GHRLex4_F) and a linker-specific reverse primer(LK).
Labs working on this lncRNA
Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia.
- Seim I, Carter SL, Herington AC, Chopin LK. Complex organisation and structure of the ghrelin antisense strand gene GHRLOS, a candidate non-coding RNA gene[J]. BMC molecular biology. 2008,9:95.
GHRLOS, GHRL-AS1, NCRNA00068
Predicted Small Protein
|Amino acid sequence||MEVSKPVPSTCQGKAQAYSLNIYSPPELVQQSWELLQKQAKSQMSASKLRERESASSLPF|