biostudies-literatureInsley PNational Institute of Neurological Disorders and StrokeNINDS NIH HHSNIH HHSNational Institute of Child Health and Human Developmente0194861https://www.ebi.ac.uk/biostudies/studies/S-EPMC5874040biostudies-literatureUnknown13(3)The Caenorhabditis elegans cell lineage is nearly invariant. Whether this stereotyped cell-division pattern promotes reproducibility in cell shapes/positions is not generally known, as manual spatiotemporal cell-shape/position alignments are labor-intensive, and fully-automated methods are not described. Here, we report automated algorithms for spatiotemporal alignments of C. elegans embryos from pre-morphogenesis to motor-activity initiation. We use sparsely-labeled green-fluorescent nuclei and a pan-nuclear red-fluorescent reporter to register consecutive imaging time points and compare embryos. Using our method, we monitor early assembly of the nerve-ring (NR) brain neuropil. While NR pioneer neurons exhibit reproducible growth kinetics and axon positions, cell-body placements are variable. Thus, pioneer-neuron axon locations, but not cell-body positions, are under selection. We also show that anterior NR displacement in cam-1/ROR Wnt-receptor mutants is not an early NR assembly defect. Our results demonstrate the utility of automated spatiotemporal alignments of C. elegans embryos, and uncover key principles guiding nervous-system development in this animal.PloS oneAutomated C. elegans embryo alignments reveal brain neuropil position invariance despite lax cell body placement.PMC5874040NS081490R35 NS105094R01NS064273HD078703R35NS105094NS095795R01NS095795R01HD078703NS064273R01NS081490Insley PShaham SfalseAutomated C. elegans embryo alignments reveal brain neuropil position invariance despite lax cell body placement.The Caenorhabditis elegans cell lineage is nearly invariant. Whether this stereotyped cell-division pattern promotes reproducibility in cell shapes/positions is not generally known, as manual spatiotemporal cell-shape/position alignments are labor-intensive, and fully-automated methods are not described. Here, we report automated algorithms for spatiotemporal alignments of C. elegans embryos from pre-morphogenesis to motor-activity initiation. We use sparsely-labeled green-fluorescent nuclei and a pan-nuclear red-fluorescent reporter to register consecutive imaging time points and compare embryos. Using our method, we monitor early assembly of the nerve-ring (NR) brain neuropil. While NR pioneer neurons exhibit reproducible growth kinetics and axon positions, cell-body placements are variable. Thus, pioneer-neuron axon locations, but not cell-body positions, are under selection. We also show that anterior NR displacement in cam-1/ROR Wnt-receptor mutants is not an early NR assembly defect. Our results demonstrate the utility of automated spatiotemporal alignments of C. elegans embryos, and uncover key principles guiding nervous-system development in this animal.2018-01-01T00:00:00Z20182024-12-04T00:32:55.163Z2019-03-26T23:25:58ZS-EPMC58740402959019310.1371/journal.pone.0194861