Transmembrane Protein 44 (TMEM44)

Tmem44, a putative transmembrane protein. TMEM44 is predicted to encode a seven transmembrane domain protein with an extracellular N-terminus and an intracellular C-terminus, but with no homology to GPCRs. TMEM44 transcripts were highly expressed in both FG and CV cynomolgus macaque taste buds and also in top and bottom portions of CV taste buds by microarray analyses. TMEM44 transcripts were not expressed in either TRPM5 or PKD1L3 taste receptor cells, and TMEM44 cells define a distinct cell population in macaque taste buds. TMEM44 signals partially colocalized with SHH signals in cells at the bottom of taste buds. TMEM44 may be expressed in cells transiting from an immature (SHH-positive) to a mature (taste receptor-positive) state and may represent an intermediate stage in taste cell development.