Primary structure of rat pulmonary surfactant protein D. cDNA and deduced amino acid sequence.
Surfactant protein D (SP-D) is a carbohydrate-binding glycoprotein containing a collagen-like domain that is synthesized by alveolar type II epithelial cells. The complete primary structure of rat SP-D has been determined by sequencing of a cloned cDNA. The protein consists of three regions: an NH2-terminal segment of 25 amino acids, a collagen-like domain consisting of 59 Gly-X-Y repeats, and a COOH-terminal carbohydrate recognition domain of 153 amino acids. There are 6 cysteine residues present in rat SP-D: 2 in the NH2-terminal noncollagenous segment and 4 in the COOH-terminal carbohydrate-binding domain. The collagenous domain contains one possible N-glycosylation site. The protein is preceded by a cleaved, NH2-terminal signal peptide. SP-D shares considerable homology with the C-type mammalian lectins. Hybridization analysis demonstrates that rat SP-D is encoded by a 1.3-kilobase mRNA which is abundant in lung and highly enriched in alveolar type II cells. Extensive homology exists between rat SP-D and bovine conglutinin.
Shimizu
H
H
Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, Denver, Colorado 80206.
Fisher
J H
JH
Papst
P
P
Benson
B
B
Lau
K
K
Mason
R J
RJ
Voelker
D R
DR
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D002417:Cattle; D003001:Cloning, Molecular; D037222:Collectins; D004247:DNA / Q000235:genetics; D015723:Gene Library; D006023:Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D037102:Lectins / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D037663:Pulmonary Surfactant-Associated Protein D; D011663:Pulmonary Surfactants / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D051381:Rats; D011916:Rats, Inbred F344; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D012712:Serum Globulins / Q000737:chemistry / Q000235:genetics
D037222:Collectins; D006023:Glycoproteins; D037102:Lectins; D037663:Pulmonary Surfactant-Associated Protein D; D011663:Pulmonary Surfactants; D012712:Serum Globulins; C024014:conglutinin; D012313:RNA; D004247:DNA