The bovine Prader-Willi/Angelman imprinted domain has four Sno-lncRNAs types

Sno-lncRNAs are intron-derived long noncoding RNAs (lncRNAs) with snoRNA ends. Sno-lncRNAs were first discovered in the human Prader-Willi (PWS)/Angelman (AS) imprinted domain. Here, we report the identification and characterization of four sno-lncRNA types (sno-lncRNA1, sno-lncRNA2, sno-lncRNA3, and sno-lncRNA4) in the bovine PWS/AS imprinted domain. Reverse transcription-PCR first determined the cDNA sequences of the four bovine sno-lncRNAs. A gene structure analysis showed that sno-lncRNA1 lacks introns, but sno-lncRNA2 and sno-lncRNA3 have one and two introns respectively. The three sno-lncRNAs have similar snoRNA ends. Moreover, the three have similar snoRNAs at their 5' and 3' ends. The head-to-tail orientation has six sno-lncRNA copies arranged between bovine SNORD116-6 and SNORD116-12. Moreover, only a copy of sno-lncRNA4 was located between SNORD116-3 and SNORD116-4. The expression of the four sno-lncRNAs was analyzed in the bovine heart, liver, spleen, lung, kidney, muscle, fat, brain, and placenta tissues. The monoallelic expression of sno-lncRNA4 was determined in bovine tissues. The results showed that the four sno-lncRNAs are widely expressed in the nine tissues, although sno-lncRNA3 and sno-lncRNA4 were undetected in the placenta. Moreover, an informative single nucleotide polymorphism (rs448706424) revealed the allelic expression of sno-lncRNA4 in exon 2 of sno-lncRNA4. The bovine genome had six copies of sno-lncRNA1, sno-lncRNA2, and sno-lncRNA3, but their allelic expression was not identified.