Regulation of Pancreatic microRNA-7 Expression

Abstract EN

Genome-encoded microRNAs (miRNAs) provide a posttranscriptional regulatory layer, which is important for pancreas development.

Differentiation of endocrine cells is controlled by a network of pancreatic transcription factors including Ngn3 and NeuroD/Beta2.

However, how specific miRNAs are intertwined into this transcriptional network is not well understood.

Here, we characterize the regulation of microRNA-7 (miR-7) by endocrine-specific transcription factors.

Our data reveal that three independent miR-7 genes are coexpressed in the pancreas.

We have identified conserved blocks upstream of pre-miR-7a-2 and pre-miR-7b and demonstrated by functional assays that they possess promoter activity, which is increased by the expression of NeuroD/Beta2.

These data suggest that the endocrine specificity of miR-7 expression is governed by transcriptional mechanisms and involves members of the pancreatic endocrine network of transcription factors.