Our mouths may be home to a multi-tasking taste bud cell that can identify four different flavours.
Most known taste bud cells can only register a specific taste, either bitter, sweet and unami; or sour and salty.
But the newly-discovered versatile cells are able to spot sweet, sour, umami and bitter tastes, an unheard of level of variety.
Taste buds are made up of three types of cells which collectively create what we experience when we eat.
Type I cells acts as support cells; Type II cells detect bitter, sweet and umami tastes; and Type III cells detect sour and salty flavors.
But studies on mice reveal a previously unknown subset of Type III cells which are ‘broadly responsive’ to all flavours.
These cells have two different signalling pathways which allow them to respond to sourness one way and sweet, bitter and umami stimuli using another.
This offers the first physical evidence of a broad-scope taste bud to back up several theories.
Although their contribution to the sense of sense can not yet be quantified, it is expected to be significant.
Their discovery provides new insight into how taste information is sent to the brain for processing, and suggests that taste buds are far more complex than we currently appreciate.
‘Taste cells can be either selective or generally responsive to stimuli which is similar to the cells in the brain that process taste information,’ commented author Dr Kathryn Medler, of the University of Buffalo.
‘Future experiments will be focused on understanding how broadly responsive taste cells contribute to taste coding.’
The research was published in the journal PLOS Genetics.