2nd Sep 2014

There are some really interesting Arabidopsis papers in the Round-up this week, including one from GARNet’s Chair, Jim Murray, a review on the role of sugar–hormone interactions in the regulation of floral signal transduction from the University of Bolton, and a fascinating Science paper describing how sieve element cells become enucleated. Enjoy!


  • Mammarella ND, Cheng Z, Qing Fu Z, Daudi A, Bolwell GP, Dong X and Ausubel FM. Apoplastic peroxidases are required for salicylic acid-mediated defense against Psuedomonas syringae. Phytochemistry, 2 August 2014. DOI: 10.1016/j.phytochem.2014.07.010.

Arsalan Daudi and Paul Bolwell from Royal Holloway worked with American colleagues on this Phytochemistry paper, which provides further detail to some previous findings regarding the effect of reduced expression of peroxidase genes. This newly published work shows that some, but not all aspects of pattern-triggered immunity in Arabidopsis are diminished in lines with reduced peroxidase expression. It was also found that salicylic acid signaling is impaired in these lines.

This paper is dedicated to the memory of Paul Bolwell, who sadly died from motor neurone disease before publication.


  • Matsoukas IG. Interplay between sugar and hormone signaling pathways modulate floral signal transduction. Frontiers in Genetics, 13 August 2014. DOI: 10.3389/fgene.2014.00218. [Open Access]

This useful review by Ianis Matsoukas at the University of Bolton highlights potential roles of sugar–hormone interactions in the regulation of floral signal transduction. It particularly emphasises Arabidopsis thaliana mutant phenotypes, and suggests possible directions for future research.


  • Forzani C, Aichinger E, Willemsen V, Laux T, Dewitte W and Murray JAH. WOX5 suppresses CYCLIN D activity to establish quiescence at the center of the root stem cell niche. Current Biology, 18 August 2014. DOI: 10.1016/j.cub.2014.07.019. [Open Access]

This paper was led by GARNet Chair Jim Murray at Cardiff University and describes findings that provide new information about the role of the transcription factor WOX5. WOX5 is known to be involved in the maintenance of a pool of stem cells at the quiescent centre (QC) of the Arabidopsis root, but the molecular mechanisms underpinning this, as well as whether WOX5 in involved in proliferation of the QC cells, has not been previously well understood. Here Jim et al propose a specific role for WOX5 in initiating and maintaining the quiescence of QC cells.


  • Miyashima Furata K, Ram Yadav S, Lehesranta S, et al. Arabidopsis NAC45/86 direct sieve element morphogenesis culminating in enucleation. Science, 22 August 2014. DOI: 10.1126/science.1253736.

Led by a Finnish group, this fascinating Science paper also involves colleagues from Belgium, more scientists from Cardiff, and from the Sainsbury Lab at the University of Cambridge. The researchers used electron microscope imaging and 3D-reconstructions to follow the development of sieve element cells and observe the regulation of the self-destruction of the nucleus. If you can get through the paywall, check out the images and movies in the supplementary data files!


  • El Zawily AM, Schwarzländer M, Finkmeier I, et al. FRIENDLY regulates mitochondrial distribution, fusion, and quality control in Arabidopsis. Plant Physiology, 27 August 2014. DOI: 10.1104/pp.114.243824. [Open Access]

This paper presents findings for the role of FRIENDLY, a protein responsible for the correct distribution of mitochondria within the cell. Scientists from Imperial College London were involved in this international work, which identified that FRIENDLY is likely to have a role in mediating inter-mitochondrial associations. Disruption of mitochondrial associations, motility and chondriome structure affects mitochondrial quality control, which in turn has repercussions for mitochondrial stress, cell death and strong growth phenotypes.