Can a gene only expresses as a lncRNA？

Question

[lewisbatmanarnold]

Is it possible that a gene is composed of exons without introns and only expresses as a lncRNA？

[Devon Ryan]

In other words, "Are there any lncRNAs with only one exon?"

[poisonAlien]

Some well known lincRNAs (such as MALAT1) are single exonic. So technically yes.

Answer 1

[PoGibas]

The GENCODE v7 catalog of human long noncoding RNAs: Analysis of their gene structure, evolution, and expression

See A:

You can easily download gencode annotation and filter genes transcripts according the number of exons.

Clumsy but works:

curl -s "ftp://ftp.sanger.ac.uk/pub/gencode/Gencode_human/release_21/gencode.v21.long_noncoding_RNAs.gtf.gz" | 
    gunzip -c | 
    awk '($3=="exon") {print $12}' | 
    sort | uniq -c | 
   awk '($1 == 1) {print $2}' | head -n 5

"ENST00000313031.2";
"ENST00000313737.5";
"ENST00000313865.6";
"ENST00000317726.4";
"ENST00000319817.3";

Answer 2

[FeiZhao]

Of course yes, indeed , some gene have more than one exon but only expresse as lncRNAs in plant.