Separate sexes have evolved repeatedly from hermaphroditic ancestors in flowering plants, and thus select taxa can provide unparalleled insight into the evolutionary dynamics of sex chromosomes that are thought to be shared by plants and animals alike. Here we ask whether two octoploid sibling species of wild strawberry-one almost exclusively dioecious (males and females), Fragaria chiloensis, and one subdioecious (males, females, and hermaphrodites), F. virginiana-share the same sex-determining chromosome. We created a genetic map of the sex chromosome and its homeologs in F. chiloensis and assessed macrosynteny between it and published maps of the proto-sex chromosome of F. virginiana and the homeologous autosome of hermaphroditic diploid species. Segregation of male and female function in our F. chiloensis mapping population confirmed that linkage and dominance relations are similar to those in F. virginiana. However, identification of the molecular markers most tightly linked to the sexdetermining locus in the two octoploid species shows that, in both, this region maps to homeologues of chromosome 6 in diploid congeners, but is located at opposite ends of their respective chromosomes.

Polyomavirus infections are common and relatively benign in the general human population but can become pathogenic in immunosuppressed patients. Because most treatments for polyomavirus-associated diseases nonspecifically target DNA replication, existing treatments for polyomavirus infection possess undesirable side effects. However, all polyomaviruses express Large Tumor Antigen (T Ag), which is unique to this virus family and may serve as a therapeutic target. Previous screening of pyrimidinone-peptoid hybrid compounds identified MAL2-11B and a MAL2-11B tetrazole derivative as inhibitors of viral replication and T Ag ATPase activity (IC50 of ~20-50μM). To improve upon this scaffold and to develop a structure-activity relationship for this new class of antiviral agents, several iterative series of MAL2-11B derivatives were synthesized. The replacement of a flexible methylene chain linker with a benzyl group or, alternatively, the addition of an ortho-methyl substituent on the biphenyl side chain in MAL2-11B yielded analogs with modestly improved IC50s (~15 μM), which retained antiviral activity. After combining both structural motifs, a new lead compound was identified that inhibited T Ag ATPase activity with an IC50 of ~5 μM. We suggest that the knowledge gained from the structure-activity relationship and a further refinement cycle of the MAL2-11B scaffold will provide a specific, novel therapeutic treatment option for polyomavirus infections and their associated diseases.

Your brain is the control center of your body; every movement, thought, and feeling that you have starts in your brain. But how does the brain do this? The work in the brain is done by neurons, a type of cell that looks like a tree with lots of branches going in all directions (look at the left side of Figure 1 to see what a neuron looks like). Thoughts and actions happen when different neurons "talk" to each other. In fact, there are neurons all over your body that get information about the world around you all the time. Neurons in your skin make you feel the things that you touch, neurons in your eyes are "turned on" by light to make you see, and neurons in the inside of your ears work when they hear noises around you. There are even neurons in your nose that react to chemicals in the air, so you can smell, and your taste buds work with neurons in your tongue that send the "Are you ready to go into the spaceship? Remember to stay very still!" This is what you hear before the bed you are lying down on starts to slide into a long, tube shaped machine. You can almost imagine that it really is a spaceship, and that you, with your helmet, earphones, and small viewing screen, are the pilot, about to blast off into outer space! Your favorite space movie starts playing on the screen, and the machine suddenly turns on, making very loud sounds like "boop-boop-bleep," and you imagine you are in an alien spaceship battle. But this is no spaceship-it is a special machine called a magnetic resonance imaging (MRI) scanner, and it can take hundreds of pictures of your brain that help us to see how your brain works and what it is made of.

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