In a paper published online in advance in Science this week, investigators at Finland's University of Helsinki and elsewhere report their identification of tumor-specific mutations in the mediator complex subunit 12 (MED12) gene in 10 of 18 uterine leiomyomas they studied using an exome sequencing approach. The team also reports its analysis of 207 additional tumors, of which 70 percent showed alterations in MED12. "The Mediator Complex is a 26-subunit transcriptional regulator that bridges DNA regulatory sequences to the RNA polymerase II initiation complex. All mutations resided in exon 2, suggesting that aberrant function of this region of MED12 contributes to tumorigenesis," the Helsinki-led team says.
In this week's issue, Yale University's Hee-Sung Park et al. report "an engineered system for specific co-translational Sep [O-Phosphoserine] incorporation — directed by UAG — into any desired position in a protein by an Escherichia coli strain that harbors a Sep-accepting transfer RNA (tRNASep), its cognate Sep-tRNA synthetase (SepRS), and an engineered EF-Tu (EF-Sep)." The team tested its system by synthesizing an activated form of human MEK1 "with either one or two Sep residues co-translationally inserted in their canonical positions," it writes in Science.
Elsewhere in the journal, researchers in France show that "a missense mutation in MED23 … co-segregates with nonsyndromic autosomal recessive intellectual disability." The French team says this mutation impairs the response of two immediate early genes — JUN and FOS — to serum mitogens "by altering the interaction between enhancer-bound transcription factors (TCF4 and ELK1, respectively) and Mediator." Further, the researchers say that their study sheds light on "the crucial role of Mediator in brain development and functioning."
In a letter to Science, Arizona State University's William Yost suggests that the National Institutes of Health "should consider restricting the amount of investigators salaries charged to a grant," or limiting salaries funded by a grant to two months, like the National Science Foundation does. "Decreasing the share of grant budgets devoted to salaries would lead to substantial savings, which could be devoted to proposals that would go unfunded otherwise," Yost says.