Title: Spemann organizer
Long Title: IUPAC Gold Book - Spemann organizer
DOI: 10.1351/goldbook.11235
Status: current

Definition
Group of cells in the amphibian embryo that is important in orientation of surrounding cells and facilitates development of the central nervous system.

Note
Cells on the ventral side of the Xenopus blastula secrete factors such as bone morphogenetic protein-4 (BMP-4) to signal the overlying ectoderm to become skin. The Spemann organizer blocks the action of BMP-4 by secreting chordin and noggin, allowing the ectoderm to develop into the brain and spinal cord by default.

Related Terms
- blastula: https://goldbook.iupac.org/terms/view/10464
- bone morphogenetic protein-4: https://goldbook.iupac.org/terms/view/10469
- central nervous system: https://goldbook.iupac.org/terms/view/10501
- chordin: https://goldbook.iupac.org/terms/view/10514
- ectoderm: https://goldbook.iupac.org/terms/view/10632
- noggin: https://goldbook.iupac.org/terms/view/11018
- spinal cord: https://goldbook.iupac.org/terms/view/11250
- ventral: https://goldbook.iupac.org/terms/view/11363

Source
- PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 806 (https://doi.org/10.1515/pac-2015-1202)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/11235/html
- json: https://goldbook.iupac.org/terms/view/11235/json
- xml: https://goldbook.iupac.org/terms/view/11235/xml

Citation: Citation: 'Spemann organizer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.11235
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Accessed: 2026-05-15T12:36:43+00:00