Molecular characterization of the porcine surfactant, pulmonary-associated protein C gene.
The surfactant, pulmonary-associated protein C (SFTPC) is a peptide secreted by the alveolar type II pneumocytes of the lung. We have characterized the porcine SFTPC gene at genomic, transcriptional, and protein levels. The porcine SFTPC is a single-copy gene on pig chromosome 14. Two transcripts were found in a newborn pig lung cDNA library: a full-length clone and a clone missing exon 5. cDNA sequence comparison revealed four synonymous and two nonsynonymous substitutions and in-frame insertions at the beginning of exon 5. Comparison of the SFTPC coding region between several mammals showed high levels of conservation. Northern blot studies showed lung-specific expression of the full-length SFTPC transcript, appearing in 50-day-old fetus and increasing during lung development. Both SFTPC transcripts were detected mainly in lung by real-time RT-PCR and they were significantly down-regulated in necrotic lungs of pigs infected with Actinobacillus pleuropneumoniae. Additionally, the protein levels were also decreased or absent in the necrotic tissue.
Cirera
S
S
Department of Animal and Veterinary Basic Sciences, Division of Genetics, The Royal Veterinary and Agricultural University, 1870 Frederiksberg C, Denmark. scs@kvl.dk
Nygård
A B
AB
Jensen
H E
HE
Skovgaard
K
K
Boye
M
M
Fredholm
M
M
D000189:Actinobacillus Infections / Q000235:genetics / Q000378:metabolism; D016977:Actinobacillus pleuropneumoniae; D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons; D005260:Female; D005333:Fetus / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D023281:Genomics; D008168:Lung / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D037721:Pulmonary Surfactant-Associated Protein C / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D034421:Sus scrofa / Q000235:genetics*
D018076:DNA, Complementary; D037721:Pulmonary Surfactant-Associated Protein C