TGF-β Signaling

Kang, Hara, Hata, Akiko, Hara Kang, Akiko Hata

The signaling pathway of TGF-β and its family member BMP has been implicated in vascular development and maintenance of homeostasis by modulating expression of small noncoding microRNAs (miRNAs). MiRNAs repress target genes, which play a critical role in regulating vascular smooth muscle cell (VSMC) growth, phenotype, and function. To understand the mechanisms by which specific miRNAs control the TGF-β and BMP signaling pathway in VSMC, it is essential to quantitate levels of specific miRNAs and their precursors whose expression are controlled by TGF-β/BMP signaling. Here, we describe a real-time quantization method for accurate and sensitive detection of miRNAs and their precursors, such as primary transcripts of miRNAs (pri-miRNAs) and precursor miRNAs (pre-miRNAs). This method requires two steps; synthesis of single-stranded complementary DNAs (cDNAs) from total RNA samples and quantization of specific pri-, pre-, or mature miRNAs by quantitative polymerase chain reaction (PCR) using a real-time PCR machine.