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Dominic Norris

Publications and source records attributed to Dominic Norris.

2 recordsLinked to original sources
PubMed2005

Breaking the left-right axis: do nodal parcels pass a signal to the left?

In mammals, left-right symmetry is broken by a mechanically driven leftward flow of liquid at the embryonic node (nodal flow). Various models have emerged explaining how this may happen. Work from Tanaka and colleagues has provided a new mechanism by which nodal flow may be breaking symmetry. They describe small membrane-bound particles, which they term nodal vesicular parcels (NVPs), that are carried to the left side of the node. In the paper, they argue how signals carried within these parcels may break L-R symmetry.

Animals↗
PubMed2004

Cited2 controls left-right patterning and heart development through a Nodal-Pitx2c pathway.

Malformations of the septum, outflow tract and aortic arch are the most common congenital cardiovascular defects and occur in mice lacking Cited2, a transcriptional coactivator of TFAP2. Here we show that Cited2(-/-) mice also develop laterality defects, including right isomerism, abnormal cardiac looping and hyposplenia, which are suppressed on a mixed genetic background. Cited2(-/-) mice lack expression of the Nodal target genes Pitx2c, Nodal and Ebaf in the left lateral plate mesoderm, where they are required for establishing laterality and cardiovascular development. CITED2 and TFAP2 were detected at the Pitx2c promoter in embryonic hearts, and they activate Pitx2c transcription in transient transfection assays. We propose that an abnormal Nodal-Pitx2c pathway represents a unifying mechanism for the cardiovascular malformations observed in Cited2(-/-) mice, and that such malformations may be the sole manifestation of a laterality defect.

Animals↗