This weeks Research Roundup includes three research and two methods papers. Firstly is work from the O’Connor and Leyser groups at SLCU that investigates the diversity of function in PIN auxin transporters between monocots and dicots. Secondly research from the Kover lab at the University of Bath has characterised the photosynthetic contribution of the inflorescence stem whilst the third paper is from the Bill Finch-Savage at the University of Warwick and looks at the effect of temperature on seed dormancy. Finally are two methods paper from the University of Warwick and Leeds that introduce protocols for the imaging of either the endoplasmic reticulum or the ultrastructure of pollen tubes.
O’Connor DL, Elton S, Ticchiarelli F, Hsia MM, Vogel JP, Leyser O (2017) Cross-species functional diversity within the PIN auxin efflux protein family. Elife. doi: 10.7554/eLife.31804
Devin O’Connor and Ottoline Leyser (SLCU) lead this research that bridges the divide between a model dicot (Arabidopsis) and a model monocot (Brachypodium)as they investigate mechanisms of auxin transport, focussed on the PIN protein family. Arabidopsis lacks a clade of PIN proteins (termed Sister-of-PIN1 (SoPIN1) that are found in other plant species. They show that Brachypodium sopin1 mutants have inflorescence defects similar to Arabidopsis pin1 mutants, a similarity of function that is confirmed by the ability of soPIN1 to rescue the phenotype of null Atpin1 plants. However Brachy PIN1 is only able to rescue a less severe Atpin1 mutant. Overall they demonstrate that PIN1 functional specificity is determined by membrane and tissue-level accumulation and transport activity. As this paper is published in Elife, the journal provides reviewer comments and in this case they show that this manuscript was initially rejected. However the authors persisted and provided a reworked manuscript that convincing the reviewers that this study was appropriate for publication in Elife. An excellent lesson in persistence!
Gnan S, Marsh T, Kover PX (2017) Inflorescence photosynthetic contribution to fitness releases Arabidopsis thaliana plants from trade-off constraints on early flowering PLoS One doi: 10.1371/journal.pone.0185835
In this study from Paula Kover’s lab at the University of Bath they investigate how the photosynthetic capacity of the Arabidopsis influoresence influences the time of flowering in a range of accessions. Interestingly after plants had flowering the authors removed rosette leaves to assess the ability of the influoresence to support future plant growth. Surprisingly there was a wide variation in general fitness following leaf removal, ranging from a growth reduction of 65% to no observed loss in fitness. These changes are due to both the differencies in the flowering time and in the number of lateral branches. This can explain how early flowering accessions can maintain fitness despite reduced vegetative growth.
Huang Z, Footitt S, Tang A, Finch-Savage WE (2017) Predicted global warming scenarios impact on the mother plant to alter seed dormancy and germination behavior in Arabidopsis Plant Cell Environ. doi: 10.1111/pce.13082
William Finch-Savage (University of Warwick) leads this investigation into the effect of temperature on seed development and dormancy. They used specially designed polyethylene tunnels that allowed in vivo variations in temperature and light conditions. Perhaps unsurprisingly they showed that temperature plays a significant role in future seed development with lower temperatures promoting dormancy but higher temperatures reduced dormancy that subsequently alters the timing of future life cycles, which has consequences for the species fitness.
Dzimitrowicz N, Breeze E, Frigerio L (2018) Long-Term Imaging of Endoplasmic Reticulum Morphology in Embryos During Seed Germination. Methods Mol Biol. doi: 10.1007/978-1-4939-7389-7_6
Lorenzo Frigerio (University of Warwick) leads this methods paper that describes the imaging of the endoplasmic reticulum over long periods during seed germination.
Ndinyanka Fabrice T, Kaech A, Barmettler G, Eichenberger C, Knox JP, Grossniklaus U, Ringli C (2017) Efficient preparation of Arabidopsis pollen tubes for ultrastructural analysis using chemical and cryo-fixation. BMC Plant Biol. doi: 10.1186/s12870-017-1136-x
Paul Knox (University of Leeds) is a co-author on this methods paper that outlines the necessary steps for efficient preparation of pollen tubes for subsequent ultrastructural analysis.