With less constraints of keeping open reading frames as in mRNAs, lncRNAs are often transcribed into multiple, alternatively spliced transcript isoforms having varying, sometimes opposing functions. For example, MEG3 gene can produce more than 10 MEG3-lncRNA transcript variants, having various p53 transactivation and tumor suppressing activities (Fig. 1) . In another example, transcript isoforms BCL-XL, BCL-XS and ENST produced from the same BCL2L1 gene have the opposite oncogenic and tumor suppressing functions .
Figure 1. Different MEG3-lncRNA transcript isoforms have varying p53 transactivation and tumor suppressing activities.
The transcript isoforms are difficult to be profiled by RNA-seq due to the insufficient read coverage divided among the transcripts and the complexity and unreliability of de novo transcripts assembly. In contrast, transcripts isoforms can be easily, unambiguously and reliably detected by specially designed probes on Arraystar lncRNA microarrays. Learn more >
 Zhang X. et al. (2010) "Maternally expressed gene 3 (MEG3) noncoding ribonucleic acid: isoform structure, expression, and functions." Endocrinology 151(3):939-47 [PMID: 20032057]
 Boise L.H. et al. (1993) "bcl-x, a bcl-2-related gene that functions as a dominant regulator of apoptotic cell death." Cell 74(4):597-608 [PMID: 8358789]