Transcription
lin-4 is transcribed from autonomous miRNA promoters and is developmentally regulated, with lin-4 miRNA accumulation occurring at the L2 stage of post-embryonic development. Additional to this is the up-regulation of endogenous lin-4 primary transcripts upon appearance of the lin-4 mature form. lin-4 is found on chromosome II in C. elegans and is complementary to sequences in the 3' untranslated region (UTR) of lin-14 mRNA, this complementary transcript containing seven binding sites along with the 9 nucleotide core element CUCAGGGAA. The lin-4:lin-14 duplex is seen to take up an unusual kinked structure, caused by induced changes in the groove dimension and base stacking due to the mismatched base pairs. This lin-4:lin-14 pair have been linked to the IGF-1 pathway in C. elegans with regards to their modification of development.
Read more about this topic: Lin-4 Micro RNA Precursor