꼬마선충 microRNA의 cleavage mechanism에 의한 pseudogene의 발현조절

Abstract

MicroRNAs (miRNA), discovered in C. elegans, are short non-coding RNAs that bind and regulate the expression of target mRNAs in plants and animals. C. elegans miRNAs bind to partially complementary sequences in the 3' untranslated region (3'UTRs) of the target mRNA, which results in translational repression through mRNA destabilization. The high-throughput sequencing of RNA cleavage fragments was performed to directly detect cleaved miRNA targets in C. elegans. Based on this analysis, mir-249 was identified as a potential miRNA that regulates a pseudogene (zk637.6) that is paralogous to asna-1(zk637.5) by cleavage mechanism with extensive, evolutionary conserved complementarity. Additionally, I validated mir-249 directed cleavage of the zk637.6 by a gene-specific 5 rapid amplification of cDNA ends (RACE) and observed notable difference in expression of zk637.6 in wild-type versus mir-249 mutant C. elegans by quantitative real-time PCR (qRT-PCR). Furthermore, the expression of zk637.6 was strongly dependent on the expression of mir-249, that is, the higher expression of mir-249 in early stage result in stronger repression of zk637.6 expression. These findings may lead to a better understanding of the biological roles of miRNAs for pseudogenes in C. elegans.