Notch activates Wnt-4 signalling to control medio-lateral patterning of the pronephros

Previous studies have highlighted a role for the Notch signalling pathway during pronephrogenesis in the amphibian Xenopus laevis, and in nephron development in the mammalian metanephros, yet a mechanism for this function remains elusive. Here, we further the understanding of how Notch signalling patterns the early X. laevis pronephros anlagen, a function that might be conserved in mammalian nephron segmentation. Our results indicate that early phase pronephric Notch signalling patterns the medio-lateral axis of the dorso-anterior pronephros anlagen, permitting the glomus and tubules to develop in isolation. We show that this novel function acts through the Notch effector gene hrt1 by upregulating expression of wnt4. Wnt-4 then patterns the proximal pronephric anlagen to establish the specific compartments that span the medio-lateral axis. We also identified pronephric expression of lunatic fringe and radical fringe that is temporally and spatially appropriate for a role in regulating Notch signalling in the dorso-anterior region of the pronephros anlagen. On the basis of these results, along with data from previous publications, we propose a mechanism by which the Notch signalling pathway regulates a Wnt-4 function that patterns the proximal pronephric anlagen

Comparing virulence of Cryphonectria parasitica isolates recovered from portions of cultures or cankers established before versus those after hypovirus innoculations

Variable recovery of hypovirulent (HV) and virulent (V) isolates from repeatedly sampled, identical chestnut blight cankers, caused by Cryphonectria parasitica, prompted this study to monitor more closely the isolate recovery over time to determine hypovirulent or virulent status. To meet the objective, laboratory and field experiments were conducted between 1998 and 2000 to recover isolates from cultures and cankers challenged with HV inoculum. Cultural studies demonstrated (1) hypovirus transfer readily occurred to actively growing colony margins, and (2) that established, virulent mycelium one-to-six weeks-old at time was unable to acquire hypovirus. Results from field studies demonstrated a significant difference in recovery of HV isolates obtained from older portions versus younger portions of cankers. The greatest recovery of HV isolates was from mycelium established just after challenge (44.4%) versus 4.6% of samples HV from the portions of cankers established four months prior to challenge. When bark plugs were sub-divided into different tissues, 20% contained both virulent and hypovirulent mycelium. Based upon this work there appears to be at least one hypothesis to explain variable recovery of HV and V isolates from identical cankers sampled over time: that rather than conversion of existing mycelium to HV status, recovery of HV isolates indicates that the subsequent fungal growth happened to be hypovirulent

Santa Fe Weekly Gazette, 03-11-1854

https://digitalrepository.unm.edu/sf_gazette_news/1200/thumbnail.jp

Santa Fe Weekly Gazette, 12-16-1865

https://digitalrepository.unm.edu/sf_gazette_news/1375/thumbnail.jp

Santa Fe Weekly Gazette, 11-01-1856

https://digitalrepository.unm.edu/sf_gazette_news/1253/thumbnail.jp

Santa Fe Weekly Gazette, 02-09-1856

https://digitalrepository.unm.edu/sf_gazette_news/1233/thumbnail.jp

Santa Fe Weekly Gazette, 11-29-1856

https://digitalrepository.unm.edu/sf_gazette_news/1257/thumbnail.jp

Santa Fe Weekly Gazette, 10-17-1868

https://digitalrepository.unm.edu/sf_gazette_news/1416/thumbnail.jp

Santa Fe Weekly Gazette, 07-15-1854

https://digitalrepository.unm.edu/sf_gazette_news/1212/thumbnail.jp