Processing of microRNA primary transcripts requires heme in mammalian cells
Sara H Weitz, Ming Gong, Ian Barr, Shimon Weiss, Feng Guo
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | NATL ACAD SCIENCES | Published : 2014
DiGeorge syndrome critical region gene 8 (DGCR8) is the RNA-binding partner protein of the nuclease Drosha. DGCR8 and Drosha recognize and cleave primary transcripts of microRNAs (pri-miRNAs) in the maturation of canonical microRNAs (miRNAs) in animals. We previously reported that human, frog, and starfish DGCR8 bind heme when expressed in Escherichia coli and that Fe(III) heme activates apoDGCR8 in reconstituted pri-miRNA processing assays. However, the physiological relevance of heme in miRNA maturation has not been clear. Here, we present a live-cell pri-miRNA processing assay that produces robust signals and faithfully indicates DGCR8 and Drosha activities. We demonstrate that all known ..View full abstract
Awarded by National Institutes of Health
Awarded by NATIONAL INSTITUTE OF GENERAL MEDICAL SCIENCES
We thank P. Sharp for sharing the pTRE-BI-red/yellow plasmid long before publication, L. Zhang for advice on measurements of heme biosynthesis and for sharing <SUP>14</SUP>C-ALA, J. Feigon for sharing equipment, Y. Chen for technical support, and R. Senturia for sharing experience and discussion. This work was supported by National Institutes of Health Grants GM080563 (to F.G.), T32GM008496 (to S.H.W.), and GM069709 (to S.W.).