Entries by Ian Street

Variation in auxin sensing guides AUX/IAA transcriptional repressor ubiquitylation and destruction

August 4, 2017 /0 Comments/in , , , /by

Subfunctionalization of duplicated genes (ohnologs) is known to occur through eventual differential gene regulation/expression and sequence divergence. Winkler et al. explore the example of the negative regulators of auxin signaling, AUX/IAA proteins IAA6 and IAA19 and how their divergent structures in the ubiquitinated and unstructured regions flanking the domain II degron differs between the two […]

Variable mesophyll conductance among soybean cultivars sets a tradeoff between photosynthesis and water-use-efficiency

August 4, 2017 /0 Comments/in , , , /by

Boosting photosynthetic efficiency in crop species has long been a goal since efficiency of photosynthesis is a critical factor in crop yield. One strategy for improving photosynthetic rates is enhancing mesophyll conductance to carbon dioxide. Tomeo and  Rosenthal examined 12 cultivars of soybean (Glycine max) under both field and control conditions to examine differences in […]

Auxin steers root cell expansion via apoplastic pH regulation in Arabidopsis thaliana

August 4, 2017 /0 Comments/in , , , /by

Barbez et al. introduce a fluorescent dye (8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt, HPTS) to track apoplastic pH in Arabidopsis roots and uncover some nuances in the auxin acid growth hypothesis. A sudden spike in auxin, perhaps counter-intuitively, causes a transient alkalization of the apoplast, preventing cell expansion. The mechanism may depend on the concentration of auxin, […]