In early online publication University College London researchers present findings on partial agonists, and how fully elucidating their function could make for better drug design. They say that in the case of ligand-activated ion channels, two members of the nicotinic family in particular, partial agonists cause a flipping conformational change in the channel that happens while the channel is still shut.
Louise Brown, the first test-tube baby, was born 30 years ago, and a news piece looks at what could happen in the next 30 years. Interviews with numerous experts reveal that most think stem cell research will advance successful derivation of germ cells from iPS cells. Says Davor Solter of the Institute of Medical Biology in Singapore, "I have no idea what kind of moral value or rights we would give to those embryos. We'll probably go through the same agonizing we did with IVF. It could be terrible to begin with, but then it'll become a fact of life." Others, like CIRM's Alan Trounson, think that it will be possible to extend women's fertility, possibly forever. Issues around these include long-term safety of the children, unknown epigenetic effects, and regulatory hurdles surrounding the research.
Two papers look at how checkpoints in cell division are regulated on a systems biology level. At Stanford, researchers examined the Start checkpoint and found that transcriptional positive feedback of the G1 cyclins Cln1 and Cln2 induces expression of the 200-gene G1/S regulon. UCSF scientists found that the switch-like behavior at anaphase is due to securin phosphoregulation, which increases the "synchrony of chromosome segregation." A related News and Views article says, "The complexity of these regulatory events raises the question of what systems-level strategies keep the process temporally coherent -- how does the maestro of the cell cycle generate a definitive downbeat?"