Integrating the forces that fold tissues

submitted by: JCB
During gastrulation, pulsed contractions of the actomyosin cytoskeleton apically constrict a strip of cells on the ventral surface of Drosophila embryos. Martin et al. examine how these contractile forces are integrated across the tissue so that it invaginates to form the embryonic mesoderm. This biosights episode presents the paper by Martin et al. from the March 8, 2010 issue of The Journal of Cell Biology, and includes an interview with lead author Adam Martin. Produced by Eun Choi and...

Systems biology of the mitotic spindle

submitted by: JCB
A novel high-throughput screening approach that combines yeast mutant arrays with high-content imaging provides fresh insights into mitotic spindle disassembly. This biosights episode presents the paper by Vizeacoumar et al. from the January 11, 2010 issue of The Journal of Cell Biology, and includes interviews with authors Brenda Andrews and Charles Boone, and JCB editorial board member John Aitchison. Produced by Eun Choi. Read the complete paper at:...

Role of the Neural Crest in Vertebrate Development and Evolution: Part 3: The Molecular Control of the Neural Crest Contribution to Craniofacial and Brain Development (36:10)

submitted by: video_collector
Further studies have shown that the NC cells which participate in facial skeletogenesis correspond to the anteriormost region of the body axis where the genes of the Hox cluster are not expressed. If the forced expression of Hoxa2, Hoxa3 and Hoxb4 (the most anteriorly expressed Hox genes) is induced in this part of the neural fold, brain development is deeply affected with anencephaly and no skeletogenesis takes place in the face which fails to develop. This phenotype is reproduced when the...

Small Regulatory RNAs May Sharpen Spatial Expression Patterns

linked profile(s): hlevine
submitted by: apryl
The precise establishment of gene expression patterns is a crucial step in development. Formation of a sharp boundary between high and low spatial expression domains requires a genetic mechanism that exhibits sensitivity, yet is robust to fluctuations, a demand that may not be easily achieved by morphogens alone. Recently, it has been demonstrated that small RNAs (and, in particular, microRNAs) play many roles in embryonic development. Whereas some RNAs are essential for embryogenesis,...
Authors: Erel Levine, Peter Mchale, Herbert Levine