cDNA cloning of ovine pulmonary SP-A, SP-B, and SP-C: isolation of two different sequences for SP-B.
Pulmonary surfactant promotes alveolar stability by lowering the surface tension at the air-liquid interface in the peripheral air spaces. The three surfactant proteins SP-A, SP-B, and SP-C contribute to dynamic surface properties involved during respiration. We have cloned and sequenced the complete cDNAs for ovine SP-A and SP-C and two distinct forms of ovine SP-B cDNAs. The nucleotide sequence of ovine SP-A cDNA consists of 1,901 bp and encodes a protein of 248 amino acids. Ovine SP-C cDNA contains 809 bp, predicting a protein of 190 amino acids. Ovine SP-B is encoded by two mRNA species, which differ by a 69-bp in-frame deletion in the region coding for the active airway protein. The larger SP-B cDNA comprises 1,660 bp, encoding a putative protein of 374 amino acids. With the sequences reported, a more complete analysis of surfactant regulation and the determination of their physiological function in vivo will be enabled.
Pietschmann
S M
SM
Department of Anesthesiology and Intensive Care Medicine, Charité Campus Virchow-Klinikum, Medical Faculty Humboldt University Berlin, D-13353 Berlin, Germany.
Pison
U
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D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D001483:Base Sequence / Q000235:genetics; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D011510:Proteolipids / Q000235:genetics*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000235:genetics*; D012756:Sheep / Q000235:genetics*
D018076:DNA, Complementary; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants