Expression of non-coding RNA AB063319 derived from Rian gene during mouse development.

The regulatory functions of many non-coding RNAs (ncRNAs) were widely recognized. However, there are very few publications on long intronic ncRNAs. The transcriptional hierarchy driving a large amount of long and short ncRNAs originated from the maternal chromosome is not clarified in the Dlk1-Dio3 imprinted clusters of mouse distal chromosome 12. Here, we only focused on the previously identified long ncRNA AB063319 which derives from the large imprinted gene Rian and contains three retained introns of Rian, and tried to unsderstand this ncRNAs part of biological functions. We used in situ hybridization and quantitative real-time RT-PCR (QRT-PCR) to characterize the spatiotemporal expression pattern of AB063319 during mouse development. The in situ hybridization results showed that AB063319 was prominently expressed in the brain at embryonic day 10.5 (E10.5) and E11.5, and abundantly expressed in brain, muscle, liver, lung and neuroendocrine tissues at E15.5. Furthermore, quantitative analyses results showed that AB063319 was gradually up-regulated from E9.5 to E18.5 and down-regulated at E19.5 during the mouse embryonic development, and AB063319 was highly expressed in tongue and brain at E12.5, E15.5 and E18.5. Alternatively, AB063319 expression was also predominantly detected in tongue and brain at mouse postnatal day 6 (P6) by semi-quantitative RT-PCR. These results indicated that AB063319, as a stable transcriptional ncRNA, might play the important roles in the morphogenesis of diverse organs and tissues, especially associated with brain and muscle development at mouse embryonic and postnatal stages.