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Review
. 2017 Aug;18(8):485-497.
doi: 10.1038/nrn.2017.68. Epub 2017 Jun 29.

Taste buds: cells, signals and synapses

Affiliations
Review

Taste buds: cells, signals and synapses

Stephen D Roper et al. Nat Rev Neurosci. 2017 Aug.

Abstract

The past decade has witnessed a consolidation and refinement of the extraordinary progress made in taste research. This Review describes recent advances in our understanding of taste receptors, taste buds, and the connections between taste buds and sensory afferent fibres. The article discusses new findings regarding the cellular mechanisms for detecting tastes, new data on the transmitters involved in taste processing and new studies that address longstanding arguments about taste coding.

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Conflict of interest statement

Competing interests statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1. Membrane proteins that transduce taste
Type 2 taste receptors (T2Rs; bitter-taste receptors) are G protein-coupled receptors (GPCRs) that have short amino termini and may function as monomers (not shown) or dimers. T1Rs (sweet-taste and umami receptors) are also GPCRs, but they have long N termini that contain bilobed (venus flytrap) domains and function as dimers that use T1R3 as an obligate subunit. T1R1–T1R3 is an umami receptor, and T1R2–T1R3 is a sweet-taste receptor. All these taste GPCRs use a common transduction pathway that includes a Gβγ-activated phospholipase C (PLCβ2) and transient receptor potential cation channel subfamily M member 5 (TRPM5). The epithelial Na channel (ENaC) has three subunits and is thought to transduce salty taste in rodents. Glucose transporter type 4 (GLUT4) — which has 12 membrane-spanning segments — transports glucose by facilitative diffusion, whereas sodium/glucose cotransporter 1 (SGLT1) is Na dependent. One or both of these transporters are hypothesized to be part of an alternative glucose-sensing pathway that is similar to the one used in pancreatic β cells.
Figure 2
Figure 2. The combinatorial model of taste coding
Individual type II taste bud cells are mostly tuned to one taste quality (for example, bitter, sweet or salty): that is, they are ‘specialists’ (umami has been omitted for clarity). The type III cells sense sour tastes and also respond secondarily to other taste stimuli via cell-to-cell (paracrine) communication within the taste bud (represented by the arrows between the taste bud cells). Thus, type III cells can be termed ‘generalists’. Some afferent ganglion neurons receive input from taste cells that respond to a single taste quality and hence would be specialist neurons. Other afferent ganglion neurons receive input from many taste cells or from type III cells and thus are multiply sensitive ‘generalist’ neurons. Moving to the CNS, sensory ganglion cells converge on hindbrain neurons in the nucleus of the solitary tract.

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References

    1. Zhang Y, et al. Coding of sweet, bitter, and umami tastes: different receptor cells sharing similar signaling pathways. Cell. 2003;112:293–301. This study demonstrates that sweet-taste and bitter-taste receptors signal via a common pathway that includes PLCβ2 and TRPM5. Mice lacking the genes that encode these signalling proteins are shown to lose taste sensitivity for sweet, bitter and umami. - PubMed
    1. Clapp TR, Yang R, Stoick CL, Kinnamon SC, Kinnamon JC. Morphologic characterization of rat taste receptor cells that express components of the phospholipase C signaling pathway. J. Comp. Neurol. 2004;468:311–321. - PubMed
    1. DeFazio RA, et al. Separate populations of receptor cells and presynaptic cells in mouse taste buds. J. Neurosci. 2006;26:3971–3980. This study uses Ca2+ imaging and single-cell reverse transcription PCR to show that cells with taste GPCRs (T1Rs and T2Rs) and their downstream effectors are distinct from taste cells that express proteins for vesicular neurotransmitter release. - PMC - PubMed
    1. Huang AL, et al. The cells and logic for mammalian sour taste detection. Nature. 2006;442:934–938. - PMC - PubMed
    1. Huang YA, Maruyama Y, Stimac R, Roper SD. Presynaptic (type III) cells in mouse taste buds sense sour (acid) taste. J. Physiol. 2008;586:2903–2912. - PMC - PubMed

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