The G/C SNP facilitates the unproductive cleavage of Microprocessor. (A) Typical structure of pri-miRNA. (B) Structures of pri-mir-146a_G and C. The green and purple arrowheads indicate the productive and unproductive cleavages, respectively. The capital letters represent pre-mir-146a. (C) Diagrams of the protein fragments used in this study. The numbers show the positions of the amino acids in each fragment, whereas the asterisks indicate the point mutations. NLS: nuclear localization signal. (D) The cleavage of pri-mir-146a_G and C by Microprocessor. The green arrowheads indicate the productive cleavages. UPC indicates the unproductive products. Five pmol of each RNA was incubated with 5 pmol Microprocessor in 10 µL pri-miRNA processing buffer. (E) Assessment of the unproductive cleavages by Microprocessor from three independent experiments (an example of which is shown in D). The two data sets were significantly different as indicated by the asterisk (*) (two-tailed t-test, P = 0.031).
