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Nodal activity in the node is discussed relative to its governing of left-right asymmetry. a genetic strategy was used to selectively remove Nodal activity from the node and embryos without it were found not to initiate molecular asymmetry in the left lateral plate mesoderm and to have multiple left-right patterning defects. The study results show that the mouse node is instrumental in initiating left-right axis specification and they show Nodal to be the key regulating morphogen in the process.

Node-specific and asymmetric nodal expression patterns are regulated by two cis-acting regulatory elements distinct from one another. The cis-regulatory elements that control nodal (ital) expression domains in early development have been analyzed. Regulatory sequences that confer node-specific expression are in an upstream region of the locus. Early expression in the epiblast and endoderm and asymmetric expression at later stages on the left side of the axis of the body are controlled by a 600-bp intronic enhancer. Developmentally regulated nodal (ital) expression at certain tissue locations in left-right (L-R) and anterior-posterior (A-P) formation is potentially controlled by shared transcriptional activators.

Research has been conducted on cell fate decisions. Results demonstrate that these decisions are governed by graded Noda1/Smad2 signals, and that Smad2-dependent signals regulate the formation of PCP precursor populations and the definitive endoderm.