Entries by Mary Williams

Different gene expression patterns in Arabidopsis grown under different densities

When grown at high density (HD), plants compete for nutrients, water and light. Guo and collaborators characterized Arabidopsis gene expression under two different growth densities: seeds sown at low density (LD), 10 cm apart and high density (HD), 2 cm apart. RNA sequencing analysis showed that only 205 of 20,660 genes were influenced by growth […]

VERNALIZATION1 modulates root system architecture in wheat and barley

Root angle determines the rooting depth and was recently associated with the VERNALIZATION1 locus. Using hexaploid wheat, Voss-Fels et al. mapped the root angle to the locus encoding the MADS-box transcription factor, which was previously associated with flowering time. The group found that the lines carrying spring allele of VRN1 produced deeper roots and had […]

Arabidopsis and crop plants differ in their 3D genome architecture ($)

Three-dimensional organization of the genome is critical for proper gene expression. Comparison of the extremely compact genome of Arabidopsis with mammalian genomes revealed reduced local intra-chromosomal contacts (also know as Topologically Associated Domains, TADs) and fewer chromatin loops in the plant model. However, very little is known about spatial chromatin organization in plants with bigger […]

Patterns and consequences of subgenome differentiation provide insights into the nature of paleopolyploidy in plants

Many plants are polyploid, meaning that instead of the normal, diploid “2n” complement of chromosomes (one from each parent), they have more than 2n. Following whole-genome duplication, redundancy can allow the duplicated regions to diverge or become silenced. In some cases, silencing occurs preferentially in one of the two parental genomes. By comparing the genomes […]

Increasing leaf vein density in rice results in an enhanced rate of photosynthesis

Increased leaf vein density is considered to be a key early step in the evolution of C4 photosynthesis.  Feldman et al. analyzed five mutants with high vein densities in the C3 crop rice to determine if photosynthetic assimilation was improved.  The mutants all had higher photosynthetic rates under saturating light, while not showing any characteristics […]

Intracellular distribution of manganese by NRAMP2 critical for photosynthesis and redox homeostasis

Manganese is a micronutrient essential for the function of several proteins including manganese superoxide dismutase (localized in the peroxisome and mitochondria) and the photosystem II reaction center (localized in the chloroplast). Mn is transported via NRAMP (Natural Resistance-Associated Macrophage Protein) transporters.  Through reverse genetics and functional complementation of yeast mutants, Alejandro and Cailliatte et al. […]

The plastid genome in Cladophorales green algae is encoded by hairpin chromosomes ($)

Plastids, the cellular sites for light reaction of photosynthesis, have a reduced genome which is circular and double stranded, ranging in the size from about 100 to 200 Kb. Some exceptions to this circular nature of plastid genomes are found in some groups of phytoplanktons, namely dinoflagellates, and as described in this work, Cladophorales green […]

Review. Artificial evolution: Creating genetic diversity in the lab ($)

Humans have been domesticating plants for 10,000 years, having an impact on the gene pools of multiple species chiefly through selective breeding approaches. Although plant domestication ensured food availability to early civilizations, plants were, and still are, mainly selected based on their morphology and physiology, which include traits such as seed or fruit size, and […]

Review: Emerging roles of cortical microtubule–membrane interactions ($)

The plant cytoskeleton forms a dynamic and complex architecture in all plant cells and comes with a myriad number of functions, from allowing intracellular transport to regulating gene expression. In this review, Yoshihisa Oda focuses on the purposes of cortical microtubule (cMT) arrays, which are anchored to the plasma membrane and form highly-ordered structures. Oda […]