All Phenotypes Hs3st3a1<tm1(KOMP)Vlcg> MGI Mouse

abnormal submandibular duct morphology ( J:320380 )

• isolated fetal submandibular gland (SMG) epithelia treated with FGF10 for 24 h show a significant reduction in Krt19 expression, suggesting a relative reduction in duct differentiation

abnormal submandibular gland branching morphogenesis ( J:320380 )

• isolated fetal SMG epithelia cultured in laminin-111 matrix with FGF10 in minimal media for 24 h show a significantly lower morphogenic index (number of endbuds x duct length x endbud width, in arbitrary units) than wild-type epithelia, indicating reduced FGF10-dependent epithelial morphogenesis

• however, intact E13 SMGs obtained from heterozygous crosses and cultured ex vivo for 48 h show no differences in endbud count (ratio of endbud number at 48 h / number at 1h) relative to wild-type SMGs

• moreover, adult SMGs from both sexes show no differences in weight and gross histology relative to wild-type SMGs

abnormal salivary gland physiology ( J:320380 )

• basal salivary gland function appears to be reduced, possibly due to myoepithelial dysfunction

• however, no alterations in salivary flow or saliva total protein concentration are noted after pilocarpine stimulation

abnormal metabolism ( J:320380 )

• heparan sulfate (HS) disaccharide analysis of adult SMGs indicates a reduction in N-sulfated and an increase in non-sulfated HS disaccharides relative to wild-type SMGs

• however, adult SMGs show normal immunostaining with 10E4 antibody (which reacts with an epitope containing N-sulfated glucosamine residues in HS) and FGF10/FGFR2b complex binding to endogenous HS

• overall glycosaminoglycans (GAG) composition is normal, with no detectable changes in the total levels of HS, chondroitin sulfate (CS), and hyaluronic acid (HA) in adult SMGs

increased drinking frequency ( J:320380 )

• unstimulated mice show an increase in the frequency of drinking behavior in a lickometer test, suggesting basal salivary hypofunction