NOSIP and its interacting protein, eNOS, in the rat trachea and lung.
Endothelial nitric oxide synthase (eNOS), the major nitric oxide (NO)-generating enzyme of the vasculature, is regulated through multiple interactions with proteins, including caveolin-1, Hsp90, Ca2+-calmodulin, and the recently discovered eNOS-interacting protein, NOSIP. Previous studies indicate that NOSIP may contribute to the intricate regulation of eNOS activity and availability. Because eNOS has been shown to be abundantly expressed in the airways, we determined the expression and cellular localization of NOSIP in rat trachea and lung by RT-PCR and immunohistochemistry and examined the interaction of NOSIP with eNOS in lung by coimmunoprecipitation. In tracheal epithelium and lung, NOSIP mRNA expression was prevalent, as shown by RT-PCR, and the corresponding protein interacted with eNOS, as demonstrated by coimmunoprecipitation. Using immunohistochemistry, we found both NOSIP and eNOS immunoreactivity in ciliated epithelial cells of trachea and bronchi, while Clara cells showed immunoreactivity for NOSIP only. NOSIP and eNOS were present in vascular and bronchial smooth muscle cells of large arteries and airways, whereas endothelial cells, as well as bronchiolar and arteriolar smooth muscle cells, exclusively stained for NOSIP. Our results point to functional role(s) of NOSIP in the control of airway and vascular diameter, mucosal secretion, NO synthesis in ciliated epithelium, and, therefore, of mucociliary and bronchial function.
König
Peter
P
Institut für Anatomie und Zellbiologie, Justus-Liebig-Universität, Giessen, Germany. peter.koenig@anatomie.med.uni-giessen.de
Dedio
Jürgen
J
Oess
Stefanie
S
Papadakis
Tamara
T
Fischer
Axel
A
Müller-Esterl
Werner
W
Kummer
Wolfgang
W
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D008168:Lung / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D009252:NADPH Dehydrogenase; D019001:Nitric Oxide Synthase / Q000096:biosynthesis* / Q000235:genetics; D052250:Nitric Oxide Synthase Type III; D009928:Organ Specificity; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D013194:Staining and Labeling; D014132:Trachea / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases
D002352:Carrier Proteins; D026901:Membrane Transport Proteins; D012333:RNA, Messenger; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D009252:NADPH Dehydrogenase; C419706:NOSIP protein, human; C497205:NOSIP protein, rat; D044767:Ubiquitin-Protein Ligases