WIKIMEDIA COMMONS, SCHNEIDER KD
A novel technique for tagging and following RNA processes in live cells promises to illuminate RNA biology the way green fluorescent protein (GFP) did for the study of proteins. The tagging method consists of short RNA sequences that bind to GFP-like fluorophores and produce a wide range of colors. These RNA-fluorophore complexes can then be fused to RNAs in the cell.
J.S. Paige et al., “RNA mimics of green fluorescent protein,” Science, 333: 642-6, 2011. Free F1000 Evaluation
Though large swaths of non-coding RNAs exist in mammals, no one had clearly explained their role. This study knocks down some of these regions and showed widespread effects on gene expression in stem cells, causing them to leave their pluripotent state or strengthening a cell’s commitment to a specific differentiated cell type.
M. Guttman et al., “lincRNAs act in the circuitry controlling pluripotency and differentiation,” Nature, 477: 295-300, 2011. Free F1000 Evaluation.
Budding yeast is one of the few species that lack RNA interference, a process in which small RNA molecules affect gene expression and is essential for most eukaryotic species. Now it’s clear why: doing without RNA interference allows the yeast to coexist with a killer virus that kills off its competitors, which apparently targets some part of that pathway.
I.A. Drinnenberg et al., “Compatibility with killer explains the rise of RNAi-deficient fungi,” Science, 333: 1592, 2011. Free F1000 Evaluation.
Chromosome segregation during meiosis and mitosis must be tightly regulated to keep in time with the cell cycle. The current study shows that this tight regulation is achieved in part by the coordinated regulation of two cross-over promoting enzymes.
J. Matos et al., “Regulatory Control of the Resolution of DNA Recombination Intermediates during Meiosis and Mitosis,” Cell, 147: 158-72, 2011. Free F1000 Evaluation.
Alternative splicing is a key molecular phenomenon that expands the diversity of structures that proteins can exhibit. This study reveals that an alternative splicing event in embryonic stem cells changes the structure of a transcription factor protein FOXP1, which in turn alters how it binds to DNA. The alternative forms of the protein help mediate cell pluripotency or differentiation.
M. Gabut et al., “An alternative splicing switch regulates embryonic stem cell pluripotency and reprogramming,” Cell, 147: 132-46, 2011. Free F1000 Evaluation.
Open reading frames, or DNA regions that lack a stop codon, often play a murky role in messenger RNA translation. This article reveals that one open reading frame in Drosophila, teams up with an RNA-binding protein called Sex-lethal, to halt the translation of mRNA.
J. Medenbach et al., “Translational control via protein-regulated upstream open reading frames,” Cell, 145:902-13, 2011. Free F1000 Evaluation.
Around the time a cell commits to dividing, it also undergoes broad changes in how genes are transcribed. But whether one of these events preceded the other wasn’t completely clear. The current study in yeast reveals that a master switch must first decide cell commitment, with genome-wide transcriptional changes occurring only after the cell fate has been determined.
U. Eser et al., “Commitment to a cellular transition precedes genome-wide transcriptional change,” Molecular Cell, 43: 515-27, 2011. Free F1000 Evaluation.
The F1000 Top 7 is a snapshot of the highest ranked articles from a 30-day period on Faculty of 1000 Molecular Biology, as calculated on October 31, 2011. Faculty Members evaluate and rate the most important papers in their field. To see the latest rankings, search the database, and read daily evaluations, visit http://f1000.com.