Cell shape determines gene expression: cardiomyocyte morphotypic transcriptomes.

Cardiomyocytes undergo considerable changes in cell shape. These can be due to hemodynamic constraints, including changes in preload and afterload conditions, or to mutations in genes important for cardiac function. These changes instigate significant changes in cellular architecture and lead to the addition of sarcomeres, at the same time or at a later stage.

Exploring parasite heterogeneity using single-cell RNA-seq reveals a gene signature among sexual stage Plasmodium falciparum parasites.

The malaria parasite has a complex lifecycle, including several events of differentiation and stage progression, while actively evading immunity in both its mosquito and human hosts. Important parasite gene expression and regulation during these events remain hidden in rare populations of cells. Here, we combine a capillary-based platform for cell isolation with single-cell RNA-sequencing to transcriptionally profile 165 single infected red blood cells (iRBCs) during the intra-erythrocytic developmental cycle (IDC).

Comparative transcriptomics reveal developmental turning points during embryogenesis of a hemimetabolous insect, the damselfly Ischnura elegans.

Identifying transcriptional changes during embryogenesis is of crucial importance for unravelling evolutionary, molecular and cellular mechanisms that underpin patterning and morphogenesis. However, comparative studies focusing on early/embryonic stages during insect development are limited to a few taxa. Drosophila melanogaster is the paradigm for insect development, whereas comparative transcriptomic studies of embryonic stages of hemimetabolous insects are completely lacking.

Tn5 transposase and tagmentation procedures for massively scaled sequencing projects.

Massively parallel DNA sequencing of thousands of samples in a single machine-run is now possible, but the preparation of the individual sequencing libraries is expensive and time-consuming. Tagmentation-based library construction, using the Tn5 transposase, is efficient for generating sequencing libraries but currently relies on undisclosed reagents, which severely limits development of novel applications and the execution of large-scale projects. Here, we present simple and robust procedures for Tn5 transposase production and optimized reaction conditions for tagmentation-based sequencing library construction.

Smart-seq2 for sensitive full-length transcriptome profiling in single cells.

Single-cell gene expression analyses hold promise for characterizing cellular heterogeneity, but current methods compromise on either the coverage, the sensitivity or the throughput. Here, we introduce Smart-seq2 with improved reverse transcription, template switching and preamplification to increase both yield and length of cDNA libraries generated from individual cells. Smart-seq2 transcriptome libraries have improved detection, coverage, bias and accuracy compared to Smart-seq libraries and are generated with off-the-shelf reagents at lower cost.

Different responses in two strains of chickens (Gallus gallus) in a magnetic orientation test.

Previous studies demonstrated that layer strain domestic chicks bred for egg production can orient using directional cues from the magnetic field; here we report that chicks from a broiler strain bred for meat production do not use magnetic cues for orientation. We imprinted both strains of chicken on a red ball and subsequently trained them in a featureless testing arena. Between rewarded trials in the geomagnetic field, we inserted unrewarded tests under the following conditions: (1) in the geomagnetic field, (2) in a magnetic field with North shifted by 90 degrees and (3) in a magnetic field with the inclination inverted.

Mitochondrial genome of Trichoplax adhaerens supports placozoa as the basal lower metazoan phylum.

Mitochondrial genomes of multicellular animals are typically 15- to 24-kb circular molecules that encode a nearly identical set of 12-14 proteins for oxidative phosphorylation and 24-25 structural RNAs (16S rRNA, 12S rRNA, and tRNAs). These genomes lack significant intragenic spacers and are generally without introns. Here, we report the complete mitochondrial genome sequence of the placozoan Trichoplax adhaerens, a metazoan with the simplest known body plan of any animal, possessing no organs, no basal membrane, and only four different somatic cell types.

The Trichoplax PaxB gene: a putative Proto-PaxA/B/C gene predating the origin of nerve and sensory cells.

Pax genes play key regulatory roles in embryonic and sensory organ development in metazoans but their evolution and ancestral functions remain widely unresolved. We have isolated a Pax gene from Placozoa, beside Porifera the only metazoan phylum that completely lacks nerve and sensory cells or organs. These simplest known metazoans also lack any kind of symmetry, organs, extracellular matrix, basal lamina, muscle cells, and main body axis.

Retinal cryptochrome in a migratory passerine bird: a possible transducer for the avian magnetic compass.

The currently discussed model of magnetoreception in birds proposes that the direction of the magnetic field is perceived by radical-pair processes in specialized photoreceptors, with cryptochromes suggested as potential candidate molecules mediating magnetic compass information. Behavioral studies have shown that magnetic compass orientation takes place in the eye and requires light from the blue-green part of the spectrum. Cryptochromes are known to absorb in the same spectral range.

The Trox-2 Hox/ParaHox gene of Trichoplax (Placozoa) marks an epithelial boundary.

Hox and ParaHox genes are implicated in axial patterning of cnidarians and bilaterians, and are thought to have originated by tandem duplication of a single "ProtoHox" gene followed by duplication of the resultant gene cluster. It is unclear what the ancestral role of Hox/ParaHox genes was before the divergence of Cnidaria and Bilateria, or what roles the postulated ProtoHox gene(s) played. Here we describe the full coding region, spatial expression and function of Trox-2, the single Hox/ParaHox-type gene identified in Trichoplax adhaerens (phylum Placozoa) and either a candidate ProtoHox or a ParaHox gene.