Loss of Hs3st3a1 or Hs3st3b1 enzymes alters heparan sulfate to reduce epithelial morphogenesis and adult salivary gland function

•Genetic deletion of either Hs3st3a1 or Hs3st3b1 in mice reduces salivary epithelial morphogenesis.•Loss of 3-O-sulfotranserases reduces basement membrane sulfation and alters HS composition.•Loss of individual 3-O-sulfotransferases alters specific HS biosynthetic transcriptional programs, suggesting Hs3st3a1 regulates Hs3st3b1.•Deletion of Hs3st3a1 or Hs3st3b1, which are highly expressed in myoepithelial cells, impairs basal salivary hypofunction.