## 3 Discussion  
In this study, we analyzed a lncRNA, _Lnc-Nr6a1_, which is induced early and abundantly during EMT. Two main isoforms are generated in response to TGF-\(\beta\), with very similar expression levels. The expression of each one is regulated by different pathways: the Inc-_Nr6a1-1_ isoform by MEK-ERK1/2 and Inc-_Nr6a1-2_ isoform by AKT, routes that are simultaneously activated by TGF-\(\beta\), and that would indicate that the isoforms could be involved in specific processes that respond to each of these routes. Each isoform has a polyadenylated transcript, but in the case of the Inc-_Nr6a1-1_ isoform it is also present as a non-polyadenylated precursor containing processed exons, miR-181a2 and miR-181b2  
Figure 8: Defective glycolysis in _Lnc-Nr6a1_-depleted cells. (**A**) Proton Efflux Rate derived from glycolysis (glycoPER) of the control, _Lnc-Nr6a1_-depleted cells and _Lnc-Nr6a1_-depleted cells overexpressing the Inc-_Nr6a1-1_ isoform. Rot/AA Rotenone/antimycin, 2-DG 2-Deoxy-D-glucose. (**B**) Plots of glycoPER quantification corrected using total ug of protein. GlycoPER is expressed as pmol/min/ug protein. Data from five independent experiments are presented as mean \(\pm\) S.D. *** \(p\) < 0.001, ** \(p\) < 0.01 by two-tailed Student’s \(t\)-test. (**C**) Enrichment of glycolytic enzymes after immunoprecipitation with enolase-1. The percent change with respect to the average spectral count for the corresponding control group is indicated. A two-group, two-tailed Student’s \(t\)-test was used to determine the statistical significance of differences between the control (C\({}_{1-3}\)) and _Lnc-Nr6a1_-depleted cell (K\({}_{1-3}\)) samples. GAPDH, glyceraldehyde 3-phophatedeshydrogenase; PKM, pyruvate kinase; ALDOA, aldolase; LDHA, lactate dehydrogenase; PGK, phosphoglycerate kinase; HK, hexokinase; PGAM, phosphoglycerate mutase; TPI, triosphosphate isomerase (**D**) A proposed model for the role of Inc-_Nr6a1-1_ as a scaffold molecule involved in the formation of a glycolytic complex. F1,6 BP, fructose-1,6-biphosphate; GA3P, 3-phosphoglycerate; 1,3 BPG, 1,3-bisphosphoglycerate; 3-PG, 3-phosphoglycerate; 2-PG, 2-phosphoglycerate; PEP, phosphoenolpyruvate. genes; as well as genomic sequences between the 3\({}^{\prime}\)-end of polyadenylated Inc-_Nr6a1-1_ and 5\({}^{\prime}\)-end of the miR-181a2 gene and the genomic sequence between both miRNAs. The transcriptional termination of the non-polyadenylated isoform and processing of pre-miR181a2 and pre-miR-181b2 would be mediated by the microprocessor complex [21; 22]. Studies reported that the cleavage of the precursor transcript by [PERSON] occurs cotranscriptionally and sometimes even before the splicing of introns [23; 24]; however, our results indicate that the cleavage of the non-polyadenylated Inc-_Nr6a1-1_ transcript by [PERSON] occurs after splicing of the introns. Regarding the resulting IncRNA molecule after processing by [PERSON] of the pre-miRNAs, the analysis of the UCSC genome browser shows the absence of ESTs between the 3\({}^{\prime}\)-end of polyadenylated Inc-_Nr6a1-1_ and 5\({}^{\prime}\) end of miRNA loci suggesting that _Inc-Nr6a1_ non-polyadenylated mature transcript resulting from processing by [PERSON] is degraded [21]; therefore, Inc-_Nr6a1-1_ and Inc-_Nr6a1-2_ isoforms and miR-181a2 and miR-181b2 would be the molecules generated from the _Inc-Nr6a1_ gene. The presence of polyadenylated and non-polyadenylated forms would make it possible to regulate the expression of these molecules, allowing high levels of one of them to be achieved without concomitant generation of high levels of another unwanted one.