While previous research has identified some miRNA targets, investigators haven't yet seen how they impact developmental processes.
"We found the first evidence that miRNAs are involved in oogenesis, and this adds an extra layer of complexity that needs to be explored if we are to understand how development is regulated," said Jonathan Minden, associate professor of biological sciences at Carnegie Mellon and one of the paper's authors.
The findings will be published online the week of Aug. 8 by the Proceedings of the National Academy of Sciences (PNAS).
"If miRNAs are missing from a developing egg, then it fails to develop to term, and the net result is infertility," said lead author Richard W. Carthew, Owen L. Coon Professor of Molecular Biology at Northwestern. "It is intriguing to think that miRNA dysfunction might be at the root cause of certain forms of infertility. We already know that miRNAs are involved in cancer and stem cell biology."
Investigators were initially surprised to find that miRNAs affected only a small fraction of expressed genes within a maturing egg. On closer inspection, they found that the genes affected by miRNAs shared common roles as regulators of protein manufacturing or turnover. These results suggest that miRNAs tightly control the abundance of proteins throughout the process of oogenesis and fertilization.
Using a proteomics tool developed at Carnegie Mellon, the scientists compared maturing fruit fly eggs. One group of eggs was missing a gene ess
Contact: Megan Fellman