Regulation of body growth by microRNAs

- miRNAs are small non-coding RNA that plays important roles in gene expression.
- Longitudinal growth at the growth plate is a key component of overall body growth.
- miR-140 and let-7 miRNA family are important regulators for growth plate.
- miRNAs regulate IGF-I signaling in vitro, which is important for cell growth.
- In vivo evidence for miRNA regulation of overall body growth and size is limited.

Regulation of body growth remains a fascinating and unresolved biological mystery. One key component of body growth is skeletal and longitudinal bone growth. Children grow taller because their bones grew longer, and the predominant driver of longitudinal bone growth is a cartilaginous structure found near the ends of long bone named the growth plate. Numerous recent studies have started to unveil the importance of microRNAs in regulation of growth plate functions, therefore contributing to regulation of linear growth. In addition to longitudinal growth, other organs in our body need to increase in size and cell number as we grow, and the regulation of organ growth involves both systemic factors like hormones; and other intrinsic mechanisms, which we are just beginning to understand. This review aims to summarize some recent important findings on how microRNAs are involved in both of these processes: the regulation of longitudinal bone growth, and the regulation of organs and overall body growth.