TY - JOUR
T1 - Quantitative functions of argonaute proteins in mammalian development
AU - Wang, Dongmei
AU - Zhang, Zhaojie
AU - O'Loughlin, Evan
AU - Lee, Thomas
AU - Houel, Stephane
AU - O'Carroll, Dónal
AU - Tarakhovsky, Alexander
AU - Ahn, Natalie G.
AU - Yi, Rui
PY - 2012/4/1
Y1 - 2012/4/1
N2 - Argonaute proteins (Ago1-4) are essential components of the microRNA-induced silencing complex and play important roles in both microRNA biogenesis and function. Although Ago2 is the only one with the slicer activity, it is not clear whether the slicer activity is a universally critical determinant for Ago2's function in mammals. Furthermore, functional specificities associated with different Argonautes remain elusive. Here we report that microRNAs are randomly sorted to individual Argonautes in mammals, independent of the slicer activity. When both Ago1 and Ago2, but not either Ago1 or Ago2 alone, are ablated in the skin, the global expression of microRNAs is significantly compromised and it causes severe defects in skin morphogenesis. Surprisingly, Ago3 is able to load microRNAs efficiently in the absence of Ago1 and Ago2, despite a significant loss of global microRNA expression. Quantitative analyses reveal that Ago2 interacts with a majority of microRNAs (60%) in the skin, compared with Ago1 (30%) and Ago3 (<10%). This distribution is highly correlated with the abundance of each Argonaute, as quantified by shotgun proteomics. The quantitative correlation between Argonautes and their associated microRNAs is conserved in human cells. Finally, we measure the absolute expression of Argonaute proteins and determine that their copy number is ~1.4 3 × 10 5 to 1.7 3 × 10 5 molecules per cell. Together, our results reveal a quantitative picture for microRNA activity in mammals.
AB - Argonaute proteins (Ago1-4) are essential components of the microRNA-induced silencing complex and play important roles in both microRNA biogenesis and function. Although Ago2 is the only one with the slicer activity, it is not clear whether the slicer activity is a universally critical determinant for Ago2's function in mammals. Furthermore, functional specificities associated with different Argonautes remain elusive. Here we report that microRNAs are randomly sorted to individual Argonautes in mammals, independent of the slicer activity. When both Ago1 and Ago2, but not either Ago1 or Ago2 alone, are ablated in the skin, the global expression of microRNAs is significantly compromised and it causes severe defects in skin morphogenesis. Surprisingly, Ago3 is able to load microRNAs efficiently in the absence of Ago1 and Ago2, despite a significant loss of global microRNA expression. Quantitative analyses reveal that Ago2 interacts with a majority of microRNAs (60%) in the skin, compared with Ago1 (30%) and Ago3 (<10%). This distribution is highly correlated with the abundance of each Argonaute, as quantified by shotgun proteomics. The quantitative correlation between Argonautes and their associated microRNAs is conserved in human cells. Finally, we measure the absolute expression of Argonaute proteins and determine that their copy number is ~1.4 3 × 10 5 to 1.7 3 × 10 5 molecules per cell. Together, our results reveal a quantitative picture for microRNA activity in mammals.
KW - Argonaute proteins
KW - Mammalian development
KW - MicroRNAs
KW - Proteomics
KW - Skin
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U2 - 10.1101/gad.182758.111
DO - 10.1101/gad.182758.111
M3 - Article
C2 - 22474261
AN - SCOPUS:84859342130
VL - 26
SP - 693
EP - 704
JO - Genes and Development
JF - Genes and Development
SN - 0890-9369
IS - 7
ER -