Ontogeny of poly(ADP-ribose) polymerase-1 in lung and developmental implications.
Poly(ADP-ribose) polymerase 1 (PARP-1) is the predominant NAD-dependent modifying enzyme in DNA repair, transcription, and apoptosis; its involvement in development has not been defined. Here, we report expression and cellular localization of PARP-1 in developing rat and human fetal lung, in vivo and in explant culture, and effects of inhibiting PARP-1 activity on lung surfactant protein (SP) expression. PARP-1 was expressed as 113-kD (p113) and 85-kD (p85) fragment in both rat and human lung. In rat lung, p113 content by Western was maximal at Embryonic Days 16-18, decreased sharply by Embryonic Day 20, and continued to decrease postnatally. p85 level was constant in the fetus and decreased postnatally. In human fetal lung, both PARP-1 mRNA expression and protein content changed little between 15 and 24 wk. Immunohistochemistry for PARP-1 in Embryonic Day 18 rat lung showed predominantly nuclear staining in most cells. In later gestation and postnatally, PARP-1 staining was primarily cytoplasmic and progressively restricted to a subset of cells, mainly bronchial epithelial and smooth muscle cells. Cell subfractionation showed that p113 localized to nucleus and p85 to cytoplasm. Inhibition of PARP-1 activity by 5-iodo-6-amino-1,2-benzopyrone in fetal rat lung explant culture did not affect SP-A and -B mRNA, but significantly increased SP-C mRNA. These findings indicate that in lung (i) PARP-1 is abundantly expressed during fetal development; (ii) p113 and p85 levels are differentially regulated; (iii) PARP-1 undergoes complex developmental changes in cellular and subcellular expression, including extensive cytoplasmic localization; and (iv) inhibition of PARP-1 activity differentially affects expression of SPs.
Ertsey
Robert
R
Cardiovascular Research Institute, Department of Pediatrics, University of California, San Francisco, USA.
Chapin
Cheryl J
CJ
Kitterman
Joseph A
JA
Scavo
Louis M
LM
D000818:Animals; D000831:Animals, Newborn; D046508:Culture Techniques; D005260:Female; D005325:Fetal Organ Maturity; D005333:Fetus / Q000033:anatomy & histology / Q000502:physiology; D005865:Gestational Age; D006801:Humans; D008168:Lung / Q000166:cytology / Q000196:embryology* / Q000201:enzymology*; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D037661:Pulmonary Surfactant-Associated Proteins / Q000235:genetics / Q000378:metabolism; D011663:Pulmonary Surfactants / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D013347:Subcellular Fractions / Q000737:chemistry / Q000378:metabolism
D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D012333:RNA, Messenger; D011065:Poly(ADP-ribose) Polymerases