title: CFTR mRNA and its truncated splice variant (TRN-CFTR) are differentially expressed during collecting duct ontogeny.
abstract: The collecting duct epithelium originates from the embryonic ureter by branching morphogenesis. Ontogeny-dependent changes of CFTR mRNA expression were assessed by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) in primary monolayer cultures of rat ureteric buds (UB) and cortical collecting ducts, microdissected at different embryonic and postnatal developmental stages. The amount of wild-type CFTR-specific PCR product in UB declined to 20% of the initial value between embryonic gestational day E15 and postnatal day P1. After birth the CFTR product increased transiently between P1 and P7 by a factor of 10 and decreased towards day P14. PCR products specific for TRN-CFTR, a truncated splice variant, however, were low in early embryonic cells, increased markedly between day E17 and P2, and reached a plateau postnatally. Therefore, mRNA encoding TRN-CFTR does not appear to have a specific embryonic-morphogenetic function. By contrast, such function is suggested for wild-type CFTR mRNA as its abundance was high in early embryonic nephrogenesis, as well as during a postnatal period shortly before branching morphogenesis is completed.
authors.affiliation: Physiologisches Institut, Ludwig-Maximilians-Universität, Munich, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Huber
authors.forename: G
authors.initials: G
authors.lastname: Braun
authors.forename: A
authors.initials: A
authors.lastname: Burger-Kentischer
authors.forename: B
authors.initials: B
authors.lastname: Reinhart
authors.forename: B
authors.initials: B
authors.lastname: Luckow
authors.forename: M
authors.initials: M
authors.lastname: Horster
mesh_terms: D017398:Alternative Splicing / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D017403:In Situ Hybridization; D007668:Kidney / Q000166:cytology / Q000196:embryology*; D007684:Kidney Tubules / Q000196:embryology; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D012965:Sodium Chloride