Related Experiment Video
Updated: Aug 3, 2026
08:01
Analysis of Developing Tooth Germ Innervation Using Microfluidic Co-culture Devices
Published on: August 14, 2015
Embryonic taste buds develop in the absence of innervation
L A Barlow1, C B Chien, R G Northcutt
1Department of Neurosciences, University of California, San Diego, La Jolla 92093, USA.
Development (Cambridge, England)
|April 1, 1996
Summary
Innervation is not required for taste bud development. Experimental evidence shows taste cells fully differentiate without nerve contact, suggesting alternative inductive signals.
Area of Science:
- Developmental biology
- Neuroscience
- Cell biology
Background:
- Taste bud development is thought to be induced by cranial nerve innervation.
- Existing experimental evidence on this role is limited and inconclusive.
Purpose of the Study:
- To experimentally determine if innervation is essential for taste cell differentiation.
- To investigate alternative mechanisms for taste bud induction.
Main Methods:
- Ectopic grafting of axolotl embryonic oropharyngeal tissue onto the trunk.
- In vitro culture of embryonic oropharyngeal tissue without neural elements.
- Morphological and immunohistochemical analysis (calretinin, serotonin).
Main Results:
- Well-differentiated taste buds formed in ectopic grafts and cultured explants lacking innervation.
- Innervating spinal nerves in grafts rarely contacted ectopic taste cells.
- Ectopic and cultured taste buds showed identical morphology and marker expression to in situ taste buds.
Conclusions:
- Taste cell differentiation occurs independently of innervation.
- Taste bud development may be induced by non-neural signals (e.g., neural crest) or intrinsic epithelial patterning.
Related Concept Videos
01:37Neural Regulation
Digestion begins with a cephalic phase that prepares the digestive system to receive food. When our brain processes visual or olfactory information about food, it triggers impulses in the cranial nerves innervating the salivary glands and stomach to prepare for food.
01:43Gustation
Gustation is a chemical sense that, along with olfaction (smell), contributes to our perception of taste. It starts with the activation of receptors by chemical compounds (tastants) dissolved in the saliva. The saliva and filiform papillae on the tongue distribute the tastants and increase their exposure to the taste receptors.
01:56Gastrulation
Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata will form...
01:51Determination
During embryogenesis, cells become progressively committed to different fates through a two-step process: specification followed by determination. Specification is demonstrated by removing a segment of an early embryo, “neutrally” culturing the tissue in vitro—for example, in a petri dish with simple medium—and then observing the derivatives. If the cultured region gives rise to cell types that it would normally generate in the embryo, this means that it is specified. In contrast, determination...
01:20Taste Buds and Receptors
Gustation, or the sense of taste, is intrinsically linked to the anatomical structures located on the tongue. This organ's surface, along with the entirety of the oral cavity, is adorned with stratified squamous epithelium. Evident on the tongue are elevated structures known as papillae (singular = papilla), which house the mechanisms for the transduction of gustatory stimuli. Four distinct types of papillae exist, each identified by their unique morphological attributes: the circumvallate,...
01:24The Physiology of Taste
The perception of a salty flavor is facilitated by sodium ions within the oral salivary fluid. Upon consumption of a salty substance, salt crystals disassemble, leading to the liberation of its constituents—Na+ and Cl- ions. These ions subsequently dissolve into the salivary fluid present in the oral cavity. The external environment of the gustatory cells experiences an elevation in Na+ concentration, thereby establishing a potent concentration gradient. This gradient propels the diffusion of...