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Robson, A.

Publications and source records attributed to Robson, A..

2 recordsLinked to original sources

Surveying insect flower visitors to crops in New Zealand and Australia

The survey of insect flower visitors to crops is an essential component in determining their effectiveness as pollinators. In most cases, different survey techniques are required for different crops because of variation in planting design, floral density, spatial distribution of flowers or where additional factors such as the variation in plant vigour are being explored. Here we provide survey techniques that have been, or are currently being employed to survey flower visitors across different crops in New Zealand and Australia. Future studies may consider the use of similar designs that will allow for increased standardisation within and between locations and studies. This will provide opportunities for improved direct comparisons between studies, and the ability to combine data sets to address broader spatial-scale questions regarding insect pollination.

ecology

RAPGEF5 regulates nuclear transport of β-catenin

Canonical Wnt signaling coordinates many critical aspects of embryonic development, while dysregulated Wnt signaling contributes to common diseases, including congenital malformations and cancer. The nuclear localization of {beta}-catenin is the defining step in pathway activation. However, despite intensive investigation, the mechanisms regulating {beta}-catenin nuclear transport remain undefined. In a patient with congenital heart disease and heterotaxy, a disorder of left-right patterning, we previously identified the guanine nucleotide exchange factor, RAPGEF5. Here, we demonstrate that RAPGEF5 regulates left-right patterning via Wnt signaling. In particular, RAPGEF5, regulates the nuclear translocation of {beta}-catenin independently of both {beta}-catenin cytoplasmic stabilization and the importin {beta}1/Ran mediated transport system. We propose a model whereby RAPGEF5 activates the nuclear GTPases, Rap1/2, to facilitate the nuclear transport of {beta}-catenin, defining a parallel nuclear transport pathway to Ran. Our results suggest new targets for modulating Wnt signaling in disease states.

developmental biology