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2264727 
Journal Article 
Abstract 
The importance of being nNOS? Unique localization of neuronal nitric oxide synthase to cilia and investigating a nitric oxide synthase-1 polymorphism in Primary Ciliary Dyskinesia 
Jackson, CL; King, J; Quinn, EN; Lackie, PM; Lucas, JS 
2010 
Yes 
American Journal of Respiratory and Critical Care Medicine
ISSN: 1073-449X
EISSN: 1535-4970 
181 
A5504 
English 
WOS:000208771003581 
is part of a larger document 3452678 Proceedings of the American Thoracic Society 2010 International Conference, May 14-19, 2010, New Orleans
Background: Within the respiratory tract, motile cilia beat in a coordinated and directional manner to power mucociliary clearance of inhaled particles and pathogens. Primary Ciliary Dyskinesia (PCD) is a multigenetic autosomal recessive disorder, in which defective cilia and impaired mucociliary clearance increases patient susceptibility to respiratory infection. Nitric Oxide (NO) production is important for normal columnar epithelial cell function and defense against infection but low nasal NO concentrations are consistently reported in PCD patients. It is suggested that mechanochemical dynein ATPases interact with NO Synthase (NOS) proteins and their molecular uncoupling may be responsible for low NO production. Genetic linkage studies have not identified the NOS genes as PCD gene candidates, yet the cause of low NO in PCD remains undetermined. NOS isoenzymes, neuronal (nNOS), inducible (iNOS) and endothelial (eNOS), encoded by the NOS1-3 genes respectively, are responsible for NO production. Whilst iNOS and eNOS have been identified in ciliated epithelium, nNOS immunoreactivity has not. Interestingly, various NOS polymorphisms are associated with low NO concentrations in other ciliopathies, moreover, reduced NO in Cystic Fibrosis, Acute Chest Syndrome and Asthma is associated particularly with more than 12 AAT allelic repeats within NOS1 intron-13.

Aims: To localize all three NOS isoenzymes, in particular nNOS, within respiratory epithelium and investigate whether the NOS1 intron-13 AAT copy number correlates with low NO in PCD.

Method: NOS isoenzymes were immuno-localized in nasal polypectomy/turbinectomy samples (n=6) by a standard ABC method with DAB chromogen detection. The NOS1 AAT repeat region (Genbank AF085229) was amplified from gDNA by polymerase chain reaction (PCR) from patients that we diagnosed as non-PCD (n=12) or PCD (n=13). PCR products were analysed by gel electrophoresis, gene sequencing and gene scanning methods. Allelic AAT copy numbers were compared with patient nasal NO concentrations (NiOx, Aerocrine) (as per Sullivan et al._2001_AJRCCM_vol.164_p.2186).

Results: nNOS, iNOS and eNOS immunoreactivity was present in ciliated epithelium. Most strikingly nNOS localized specifically to the ciliated compartment, a novel finding confirmed by peptide absorbtion. PCD and non-PCD patients exhibited mean nasal NO concentrations of 33ppb (SEM±5) and 594ppb (SEM±113) respectively (p=0.0001). The allelic sum of NOS1 AAT repeats did not correlate with nasal NO concentrations in PCD (R^2 =0.06) and non-PCD patients (R^2=0.09).

Conclusions: The nNOS isoenzyme localized to the apex of ciliated epithelium and we speculate nNOS may be important for ciliary NO activity within epithelium. The NOS1 AAT microsatellite polymorphism was not associated with nasal NO concentration in PCD. 
American Thoracic Society 2010 International Conference 
New Orleans, LA 
May 14-19, 2010