APOA1-AS, an antisense transcript of APOA1, functions as a negative transcpritional regulator of APOA1 by modulating distinct histone methylation patterns.
APOA1-AS: Apolipoprotein A-1 antisense RNA(HGNC nomenclature)
APOA1-AS is transcribed from the positive strand of chromosome 11 and has two exons, positioned ~20kb apart. It shares a 123 nucleotide-long region overlapping with the fourth exon of APOA1 mRNA.(Figure 1)
APOA1-AS functions in cis to modulate histone methylation patterns of APOA1, through the recruitment of LSD1 and PRC2. Targeting APOA1-AS using short antisense oligonucleotides will enhance APOA1's expressopn level. APOA1-AS also regulates the transcription of APOC3 and APOA4, which are located in close proximity on the chromatin. 
APOA1 and APOA1-AS are expressed in all tissues examined, but there their expression levels are quite different. APOA1 mRNA’s expression level is highest in liver, small intestine and colon, while APOA1-AS is highly expressed in ovary, cervix, testis and thyroid. The ratio of APOA1/APOA1-AS varies among the tissues examined.(Figure 2) 
Labs working on this lncRNA
Center for Therapeutic Innovation & Department of Psychiatry and Behavioral Sciences, University of Miami Miller School of Medicine .
- Halley P, Kadakkuzha BM, Faghihi MA, Magistri M, Zeier Z, Khorkova O, et al. Regulation of the apolipoprotein gene cluster by a long noncoding RNA[J]. Cell reports. 2014,6(1):222-30.