What is the normal function of micro RNA 122?

 microRNA 122 (miR122) is a 23nt-long RNA that is specifically expressed in livers. miR122 is known as a strong positive regulator of Hepatitis C virus (HCV) growth in liver-associated tissues and cells. miR122 binding site within HCV genome is identified at the proximal upper side of IRES that locates near the 5' end of positive sense genome. miR122 is considered to be involved in the stability of HCV genome by binding to the RNA, which facilitate the efficient replication of HCV genome. Although miR122 is well known from a point of view regarding the regulating mechanism of HCV infection, the normal function of miR122 in livers has not been well examined. I learned one of the normal functions of miR122 in liver from a seminar today. I hope to introduce the contents of the seminar here, whereas I won't do it because it may be a confidential result.