Nucleotide and deduced amino acid sequence of the hydrophobic surfactant protein SP-C from rat: expression in alveolar type II cells and homology with SP-C from other species.
Pulmonary surfactant lowers surface tension in the lung. Its deficiency leads to the severe physiologic abnormalities seen in the respiratory distress syndrome. The hydrophobic surfactant proteins, SP-B and SP-C, appear to be especially important in the surface-spreading characteristics of pulmonary surfactant. We report the nucleotide sequence of cDNA clones for rat SP-C and compare the deduced amino acid sequence for SP-C from several species. A highly conserved domain exists within the confines of mature human SP-C. An Eisenberg plot of this region predicts a membrane-associated helix. We also demonstrate by Northern analysis the tissue-specific expression of SP-C. A comparison of signal strength between total lung RNA and RNA derived from isolated type II cells supports the idea that most SP-C messenger RNA in total lung can be accounted for by that present in alveolar type II cells.
Fisher
J H
JH
Department of Medicine, University of Colorado Health Sciences Center, Denver 80262.
Shannon
J M
JM
Hofmann
T
T
Mason
R J
RJ
D000595:Amino Acid Sequence; D000818:Animals; D001059:Apoproteins / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000302:isolation & purification; D004285:Dogs; D006801:Humans; D008969:Molecular Sequence Data; D009928:Organ Specificity; D011650:Pulmonary Alveoli / Q000032:analysis*; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000235:genetics* / Q000302:isolation & purification; D051381:Rats; D012689:Sequence Homology, Nucleic Acid; D013329:Structure-Activity Relationship
D001059:Apoproteins; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; C046616:pulmonary surfactant apoprotein; D004247:DNA